Viruses containing two or more pieces of nucleic acid (segmented genome) from different parents. Such viruses are produced in cells coinfected with different strains of a given virus.
The type species of the genus INFLUENZAVIRUS A that causes influenza and other diseases in humans and animals. Antigenic variation occurs frequently between strains, allowing classification into subtypes and variants. Transmission is usually by aerosol (human and most non-aquatic hosts) or waterborne (ducks). Infected birds shed the virus in their saliva, nasal secretions, and feces.
A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 3 and neuraminidase 2. The H3N2 subtype was responsible for the Hong Kong flu pandemic of 1968.
A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 5 and neuraminidase 1. The H5N1 subtype, frequently referred to as the bird flu virus, is endemic in wild birds and very contagious among both domestic (POULTRY) and wild birds. It does not usually infect humans, but some cases have been reported.
Semidomesticated variety of European polecat much used for hunting RODENTS and/or RABBITS and as a laboratory animal. It is in the subfamily Mustelinae, family MUSTELIDAE.
Virus diseases caused by the ORTHOMYXOVIRIDAE.
A subtype of INFLUENZA A VIRUS with the surface proteins hemagglutinin 1 and neuraminidase 1. The H1N1 subtype was responsible for the Spanish flu pandemic of 1918.
A serotype of ORTHOREOVIRUS, MAMMALIAN causing serious pathology in laboratory rodents, characterized by diarrhea, oily coat, jaundice, and multiple organ involvement.
A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 9 and neuraminidase 2. The H9N2 subtype usually infects domestic birds (POULTRY) but there have been some human infections reported.
A species in the ORTHOBUNYAVIRUS genus of the family BUNYAVIRIDAE. Serotypes are found in temperate and arctic regions and each is closely associated with a single species of vector mosquito. The vertebrate hosts are usually small mammals but several serotypes infect humans.
The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.
Membrane glycoproteins from influenza viruses which are involved in hemagglutination, virus attachment, and envelope fusion. Fourteen distinct subtypes of HA glycoproteins and nine of NA glycoproteins have been identified from INFLUENZA A VIRUS; no subtypes have been identified for Influenza B or Influenza C viruses.
The functional hereditary units of VIRUSES.
Infection of domestic and wild fowl and other BIRDS with INFLUENZA A VIRUS. Avian influenza usually does not sicken birds, but can be highly pathogenic and fatal in domestic POULTRY.
A genus of the family CEBIDAE consisting of four species: S. boliviensis, S. orstedii (red-backed squirrel monkey), S. sciureus (common squirrel monkey), and S. ustus. They inhabit tropical rain forests in Central and South America. S. sciureus is used extensively in research studies.
A genus of REOVIRIDAE, causing acute gastroenteritis in BIRDS and MAMMALS, including humans. Transmission is horizontal and by environmental contamination. Seven species (Rotaviruses A thru G) are recognized.
An acute viral infection in humans involving the respiratory tract. It is marked by inflammation of the NASAL MUCOSA; the PHARYNX; and conjunctiva, and by headache and severe, often generalized, myalgia.
Live vaccines prepared from microorganisms which have undergone physical adaptation (e.g., by radiation or temperature conditioning) or serial passage in laboratory animal hosts or infected tissue/cell cultures, in order to produce avirulent mutant strains capable of inducing protective immunity.
An enzyme that catalyzes the hydrolysis of alpha-2,3, alpha-2,6-, and alpha-2,8-glycosidic linkages (at a decreasing rate, respectively) of terminal sialic residues in oligosaccharides, glycoproteins, glycolipids, colominic acid, and synthetic substrate. (From Enzyme Nomenclature, 1992)
Poly or pyrophosphates of tin. In conjunction with radioactive technetium these compounds are used as bone-scanning agents and in scintigraphy to diagnose myocardial and cerebral infarction.
Proteins found in any species of virus.
A genus of the family REOVIRIDAE infecting vertebrates only. Transmission is horizontal and infected species include humans, birds, cattle, monkeys, sheep, swine, baboons, and bats. MAMMALIAN ORTHOREOVIRUS is the type species.
Infections produced by reoviruses, general or unspecified.
Ribonucleic acid that makes up the genetic material of viruses.
A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 1 and neuraminidase 2. It is endemic in both human and pig populations.
An alloy used in restorative dentistry that contains mercury, silver, tin, copper, and possibly zinc.
Proteins that form the CAPSID of VIRUSES.
Substances elaborated by viruses that have antigenic activity.
Specific hemagglutinin subtypes encoded by VIRUSES.
A family of viruses, mainly arboviruses, consisting of a single strand of RNA. Virions are enveloped particles 90-120 nm diameter. The complete family contains over 300 members arranged in five genera: ORTHOBUNYAVIRUS; HANTAVIRUS; NAIROVIRUS; PHLEBOVIRUS; and TOSPOVIRUS.
Vaccines used to prevent infection by viruses in the family ORTHOMYXOVIRIDAE. It includes both killed and attenuated vaccines. The composition of the vaccines is changed each year in response to antigenic shifts and changes in prevalence of influenza virus strains. The vaccine is usually bivalent or trivalent, containing one or two INFLUENZAVIRUS A strains and one INFLUENZAVIRUS B strain.
The relationships of groups of organisms as reflected by their genetic makeup.
The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.
Domesticated birds raised for food. It typically includes CHICKENS; TURKEYS, DUCKS; GEESE; and others.
The type species of ORTHOPOXVIRUS, related to COWPOX VIRUS, but whose true origin is unknown. It has been used as a live vaccine against SMALLPOX. It is also used as a vector for inserting foreign DNA into animals. Rabbitpox virus is a subspecies of VACCINIA VIRUS.
Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.
Warm-blooded VERTEBRATES possessing FEATHERS and belonging to the class Aves.
The expelling of virus particles from the body. Important routes include the respiratory tract, genital tract, and intestinal tract. Virus shedding is an important means of vertical transmission (INFECTIOUS DISEASE TRANSMISSION, VERTICAL).
An enzyme that catalyses RNA-template-directed extension of the 3'- end of an RNA strand by one nucleotide at a time, and can initiate a chain de novo. (Enzyme Nomenclature, 1992, p293)
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.
Agglutination of ERYTHROCYTES by a virus.
A cultured line of C3H mouse FIBROBLASTS that do not adhere to one another and do not express CADHERINS.
Diseases of birds which are raised as a source of meat or eggs for human consumption and are usually found in barnyards, hatcheries, etc. The concept is differentiated from BIRD DISEASES which is for diseases of birds not considered poultry and usually found in zoos, parks, and the wild.
Proteins found mainly in icosahedral DNA and RNA viruses. They consist of proteins directly associated with the nucleic acid inside the NUCLEOCAPSID.
The outer protein protective shell of a virus, which protects the viral nucleic acid.
Infection with any of the rotaviruses. Specific infections include human infantile diarrhea, neonatal calf diarrhea, and epidemic diarrhea of infant mice.
Process of growing viruses in live animals, plants, or cultured cells.
Established cell cultures that have the potential to propagate indefinitely.
A general term for diseases produced by viruses.
A species of POLYOMAVIRUS originally isolated from Rhesus monkey kidney tissue. It produces malignancy in human and newborn hamster kidney cell cultures.
A species of ARENAVIRUS, part of the Old World Arenaviruses (ARENAVIRUSES, OLD WORLD), and the etiologic agent of LASSA FEVER. LASSA VIRUS is a common infective agent in humans in West Africa. Its natural host is the multimammate mouse Mastomys natalensis.
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
Immunoglobulins produced in response to VIRAL ANTIGENS.
The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.
Viruses parasitic on plants higher than bacteria.
The complete genetic complement contained in a DNA or RNA molecule in a virus.
Vaccines or candidate vaccines used to prevent infection with ROTAVIRUS.
Viruses whose nucleic acid is DNA.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
Viruses which lack a complete genome so that they cannot completely replicate or cannot form a protein coat. Some are host-dependent defectives, meaning they can replicate only in cell systems which provide the particular genetic function which they lack. Others, called SATELLITE VIRUSES, are able to replicate only when their genetic defect is complemented by a helper virus.
Diseases of domestic swine and of the wild boar of the genus Sus.
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
The use of techniques that produce a functional MUTATION or an effect on GENE EXPRESSION of a specific gene of interest in order to identify the role or activity of the gene product of that gene.
Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.
The type species of ALPHAVIRUS normally transmitted to birds by CULEX mosquitoes in Egypt, South Africa, India, Malaya, the Philippines, and Australia. It may be associated with fever in humans. Serotypes (differing by less than 17% in nucleotide sequence) include Babanki, Kyzylagach, and Ockelbo viruses.
Proteins conjugated with nucleic acids.
The type species of MORBILLIVIRUS and the cause of the highly infectious human disease MEASLES, which affects mostly children.
A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 5 and neuraminidase 2. The H5N2 subtype has been found to be highly pathogenic in chickens.
The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.
The type species of LYSSAVIRUS causing rabies in humans and other animals. Transmission is mostly by animal bites through saliva. The virus is neurotropic multiplying in neurons and myotubes of vertebrates.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
The type species of ORBIVIRUS causing a serious disease in sheep, especially lambs. It may also infect wild ruminants and other domestic animals.
A CELL LINE derived from the kidney of the African green (vervet) monkey, (CERCOPITHECUS AETHIOPS) used primarily in virus replication studies and plaque assays.
A genus of the family BUNYAVIRIDAE containing over 150 viruses, most of which are transmitted by mosquitoes or flies. They are arranged in groups defined by serological criteria, each now named for the original reference species (previously called serogroups). Many species have multiple serotypes or strains.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
The measurement of infection-blocking titer of ANTISERA by testing a series of dilutions for a given virus-antiserum interaction end-point, which is generally the dilution at which tissue cultures inoculated with the serum-virus mixtures demonstrate cytopathology (CPE) or the dilution at which 50% of test animals injected with serum-virus mixtures show infectivity (ID50) or die (LD50).
Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE.
A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.
The type species of the genus ORTHOHEPADNAVIRUS which causes human HEPATITIS B and is also apparently a causal agent in human HEPATOCELLULAR CARCINOMA. The Dane particle is an intact hepatitis virion, named after its discoverer. Non-infectious spherical and tubular particles are also seen in the serum.
Virus diseases caused by the BUNYAVIRIDAE.
A species of FLAVIVIRUS, one of the Japanese encephalitis virus group (ENCEPHALITIS VIRUSES, JAPANESE). It can infect birds and mammals. In humans, it is seen most frequently in Africa, Asia, and Europe presenting as a silent infection or undifferentiated fever (WEST NILE FEVER). The virus appeared in North America for the first time in 1999. It is transmitted mainly by CULEX spp mosquitoes which feed primarily on birds, but it can also be carried by the Asian Tiger mosquito, AEDES albopictus, which feeds mainly on mammals.
A species in the ORTHOBUNYAVIRUS genus of the family BUNYAVIRIDAE. A large number of serotypes or strains exist in many parts of the world. They are transmitted by mosquitoes and infect humans in some areas.
A group of viruses in the PNEUMOVIRUS genus causing respiratory infections in various mammals. Humans and cattle are most affected but infections in goats and sheep have also been reported.
A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 7 and neuraminidase 7. The H7N7 subtype produced an epidemic in 2003 which was highly pathogenic among domestic birds (POULTRY). Some infections in humans were reported.
A group of disorders resulting from the abnormal proliferation of and tissue infiltration by LANGERHANS CELLS which can be detected by their characteristic Birbeck granules (X bodies), or by monoclonal antibody staining for their surface CD1 ANTIGENS. Langerhans-cell granulomatosis can involve a single organ, or can be a systemic disorder.
Aquaporin 2 is a water-specific channel protein that is expressed in KIDNEY COLLECTING DUCTS. The translocation of aquaporin 2 to the apical PLASMA MEMBRANE is regulated by VASOPRESSIN, and MUTATIONS in AQP2 have been implicated in a variety of kidney disorders including DIABETES INSIPIDUS.
Serologic tests in which a known quantity of antigen is added to the serum prior to the addition of a red cell suspension. Reaction result is expressed as the smallest amount of antigen which causes complete inhibition of hemagglutination.
The type species of VESICULOVIRUS causing a disease symptomatically similar to FOOT-AND-MOUTH DISEASE in cattle, horses, and pigs. It may be transmitted to other species including humans, where it causes influenza-like symptoms.
A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 2 and neuraminidase 2. The H2N2 subtype was responsible for the Asian flu pandemic of 1957.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
A form of intestinal obstruction caused by the PROLAPSE of a part of the intestine into the adjoining intestinal lumen. There are four types: colic, involving segments of the LARGE INTESTINE; enteric, involving only the SMALL INTESTINE; ileocecal, in which the ILEOCECAL VALVE prolapses into the CECUM, drawing the ILEUM along with it; and ileocolic, in which the ileum prolapses through the ileocecal valve into the COLON.
The ability of a pathogenic virus to lie dormant within a cell (latent infection). In eukaryotes, subsequent activation and viral replication is thought to be caused by extracellular stimulation of cellular transcription factors. Latency in bacteriophage is maintained by the expression of virally encoded repressors.
A family of RNA viruses causing INFLUENZA and other diseases. There are five recognized genera: INFLUENZAVIRUS A; INFLUENZAVIRUS B; INFLUENZAVIRUS C; ISAVIRUS; and THOGOTOVIRUS.
A subtype of INFLUENZA A VIRUS with the surface proteins hemagglutinin 7 and neuraminidase 9. This avian origin virus was first identified in humans in 2013.
Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.
A family of RNA viruses naturally infecting rodents and consisting of one genus (ARENAVIRUS) with two groups: Old World Arenaviruses (ARENAVIRUSES, OLD WORLD) and New World Arenaviruses (ARENAVIRUSES, NEW WORLD). Infection in rodents is persistent and silent. Vertical transmission is through milk-, saliva-, or urine-borne routes. Horizontal transmission to humans, monkeys, and other animals is important.
Viruses that produce tumors.
Species of the genus LENTIVIRUS, subgenus primate immunodeficiency viruses (IMMUNODEFICIENCY VIRUSES, PRIMATE), that induces acquired immunodeficiency syndrome in monkeys and apes (SAIDS). The genetic organization of SIV is virtually identical to HIV.
Deoxyribonucleic acid that makes up the genetic material of viruses.
Resin from wood of certain species of GUAIACUM. It is used as clinical reagent for occult blood.
An acute febrile human disease caused by the LASSA VIRUS.
The type species of RUBULAVIRUS that causes an acute infectious disease in humans, affecting mainly children. Transmission occurs by droplet infection.
A species of RESPIROVIRUS also called hemadsorption virus 2 (HA2), which causes laryngotracheitis in humans, especially children.
Viral proteins that are components of the mature assembled VIRUS PARTICLES. They may include nucleocapsid core proteins (gag proteins), enzymes packaged within the virus particle (pol proteins), and membrane components (env proteins). These do not include the proteins encoded in the VIRAL GENOME that are produced in infected cells but which are not packaged in the mature virus particle,i.e. the so called non-structural proteins (VIRAL NONSTRUCTURAL PROTEINS).
Viruses which produce a mottled appearance of the leaves of plants.
The infective system of a virus, composed of the viral genome, a protein core, and a protein coat called a capsid, which may be naked or enclosed in a lipoprotein envelope called the peplos.
An epithelial cell line derived from a kidney of a normal adult female dog.
Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.
A species in the genus HEPATOVIRUS containing one serotype and two strains: HUMAN HEPATITIS A VIRUS and Simian hepatitis A virus causing hepatitis in humans (HEPATITIS A) and primates, respectively.
A species of ALPHAVIRUS isolated in central, eastern, and southern Africa.
Group of alpharetroviruses (ALPHARETROVIRUS) producing sarcomata and other tumors in chickens and other fowl and also in pigeons, ducks, and RATS.
Agents used in the prophylaxis or therapy of VIRUS DISEASES. Some of the ways they may act include preventing viral replication by inhibiting viral DNA polymerase; binding to specific cell-surface receptors and inhibiting viral penetration or uncoating; inhibiting viral protein synthesis; or blocking late stages of virus assembly.
The binding of virus particles to receptors on the host cell surface. For enveloped viruses, the virion ligand is usually a surface glycoprotein as is the cellular receptor. For non-enveloped viruses, the virus CAPSID serves as the ligand.
A species of POLYOMAVIRUS apparently infecting over 90% of children but not clearly associated with any clinical illness in childhood. The virus remains latent in the body throughout life and can be reactivated under certain circumstances.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Infections produced by oncogenic viruses. The infections caused by DNA viruses are less numerous but more diverse than those caused by the RNA oncogenic viruses.
Viruses whose taxonomic relationships have not been established.
A species of POLYOMAVIRUS, originally isolated from the brain of a patient with progressive multifocal leukoencephalopathy. The patient's initials J.C. gave the virus its name. Infection is not accompanied by any apparent illness but serious demyelinating disease can appear later, probably following reactivation of latent virus.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
The type species of ALPHARETROVIRUS producing latent or manifest lymphoid leukosis in fowl.
The degree of similarity between sequences. Studies of AMINO ACID SEQUENCE HOMOLOGY and NUCLEIC ACID SEQUENCE HOMOLOGY provide useful information about the genetic relatedness of genes, gene products, and species.
INFLAMMATION of any segment of the GASTROINTESTINAL TRACT from ESOPHAGUS to RECTUM. Causes of gastroenteritis are many including genetic, infection, HYPERSENSITIVITY, drug effects, and CANCER.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses.
The type species of RESPIROVIRUS in the subfamily PARAMYXOVIRINAE. It is the murine version of HUMAN PARAINFLUENZA VIRUS 1, distinguished by host range.
A strain of Murine leukemia virus (LEUKEMIA VIRUS, MURINE) arising during the propagation of S37 mouse sarcoma, and causing lymphoid leukemia in mice. It also infects rats and newborn hamsters. It is apparently transmitted to embryos in utero and to newborns through mother's milk.
Suspensions of attenuated or killed viruses administered for the prevention or treatment of infectious viral disease.
Insertion of viral DNA into host-cell DNA. This includes integration of phage DNA into bacterial DNA; (LYSOGENY); to form a PROPHAGE or integration of retroviral DNA into cellular DNA to form a PROVIRUS.
The type species of the FLAVIVIRUS genus. Principal vector transmission to humans is by AEDES spp. mosquitoes.
A genus of the family HERPESVIRIDAE, subfamily ALPHAHERPESVIRINAE, consisting of herpes simplex-like viruses. The type species is HERPESVIRUS 1, HUMAN.
The type species of TOBAMOVIRUS which causes mosaic disease of tobacco. Transmission occurs by mechanical inoculation.
A species of gram-negative bacteria in the genus VIBRIO, isolated from SHELLFISH, as well as from human diarrheal stools and ear infections.
Genotypic differences observed among individuals in a population.
Pneumovirus infections caused by the RESPIRATORY SYNCYTIAL VIRUSES. Humans and cattle are most affected but infections in goats and sheep have been reported.
The type species of LEPORIPOXVIRUS causing infectious myxomatosis, a severe generalized disease, in rabbits. Tumors are not always present.
Inactivation of viruses by non-immune related techniques. They include extremes of pH, HEAT treatment, ultraviolet radiation, IONIZING RADIATION; DESICCATION; ANTISEPTICS; DISINFECTANTS; organic solvents, and DETERGENTS.
Virus diseases caused by the BIRNAVIRIDAE.
A species of ORTHOPOXVIRUS that is the etiologic agent of COWPOX. It is closely related to but antigenically different from VACCINIA VIRUS.
Visible morphologic changes in cells infected with viruses. It includes shutdown of cellular RNA and protein synthesis, cell fusion, release of lysosomal enzymes, changes in cell membrane permeability, diffuse changes in intracellular structures, presence of viral inclusion bodies, and chromosomal aberrations. It excludes malignant transformation, which is CELL TRANSFORMATION, VIRAL. Viral cytopathogenic effects provide a valuable method for identifying and classifying the infecting viruses.
A species of ORTHOPOXVIRUS causing infections in humans. No infections have been reported since 1977 and the virus is now believed to be virtually extinct.
A country spanning from central Asia to the Pacific Ocean.
The type species of PNEUMOVIRUS and an important cause of lower respiratory disease in infants and young children. It frequently presents with bronchitis and bronchopneumonia and is further characterized by fever, cough, dyspnea, wheezing, and pallor.
Vaccines in which the infectious microbial nucleic acid components have been destroyed by chemical or physical treatment (e.g., formalin, beta-propiolactone, gamma radiation) without affecting the antigenicity or immunogenicity of the viral coat or bacterial outer membrane proteins.
The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A group of viral diseases of diverse etiology but having many similar clinical characteristics; increased capillary permeability, leukopenia, and thrombocytopenia are common to all. Hemorrhagic fevers are characterized by sudden onset, fever, headache, generalized myalgia, backache, conjunctivitis, and severe prostration, followed by various hemorrhagic symptoms. Hemorrhagic fever with kidney involvement is HEMORRHAGIC FEVER WITH RENAL SYNDROME.
A species of ALPHAVIRUS causing an acute dengue-like fever.
The type species in the genus NOROVIRUS, first isolated in 1968 from the stools of school children in Norwalk, Ohio, who were suffering from GASTROENTERITIS. The virions are non-enveloped spherical particles containing a single protein. Multiple strains are named after the places where outbreaks have occurred.
Serological reactions in which an antiserum against one antigen reacts with a non-identical but closely related antigen.
A collection of single-stranded RNA viruses scattered across the Bunyaviridae, Flaviviridae, and Togaviridae families whose common property is the ability to induce encephalitic conditions in infected hosts.
Biological properties, processes, and activities of VIRUSES.
The type species of SIMPLEXVIRUS causing most forms of non-genital herpes simplex in humans. Primary infection occurs mainly in infants and young children and then the virus becomes latent in the dorsal root ganglion. It then is periodically reactivated throughout life causing mostly benign conditions.

Yellow fever/Japanese encephalitis chimeric viruses: construction and biological properties. (1/699)

A system has been developed for generating chimeric yellow fever/Japanese encephalitis (YF/JE) viruses from cDNA templates encoding the structural proteins prM and E of JE virus within the backbone of a molecular clone of the YF17D strain. Chimeric viruses incorporating the proteins of two JE strains, SA14-14-2 (human vaccine strain) and JE Nakayama (JE-N [virulent mouse brain-passaged strain]), were studied in cell culture and laboratory mice. The JE envelope protein (E) retained antigenic and biological properties when expressed with its prM protein together with the YF capsid; however, viable chimeric viruses incorporating the entire JE structural region (C-prM-E) could not be obtained. YF/JE(prM-E) chimeric viruses grew efficiently in cells of vertebrate or mosquito origin compared to the parental viruses. The YF/JE SA14-14-2 virus was unable to kill young adult mice by intracerebral challenge, even at doses of 10(6) PFU. In contrast, the YF/JE-N virus was neurovirulent, but the phenotype resembled parental YF virus rather than JE-N. Ten predicted amino acid differences distinguish the JE E proteins of the two chimeric viruses, therefore implicating one or more residues as virus-specific determinants of mouse neurovirulence in this chimeric system. This study indicates the feasibility of expressing protective antigens of JE virus in the context of a live, attenuated flavivirus vaccine strain (YF17D) and also establishes a genetic system for investigating the molecular basis for neurovirulence determinants encoded within the JE E protein.  (+info)

Late domain function identified in the vesicular stomatitis virus M protein by use of rhabdovirus-retrovirus chimeras. (2/699)

Little is known about the mechanisms used by enveloped viruses to separate themselves from the cell surface at the final step of budding. However, small sequences in the Gag proteins of several retroviruses (L domains) have been implicated in this process. A sequence has been identified in the M proteins of rhabdoviruses that closely resembles the PPPPY motif in the L domain of Rous sarcoma virus (RSV), an avian retrovirus. To evaluate whether the PPPY sequence in vesicular stomatitis virus (VSV) M protein has an activity analogous to that of the retroviral sequence, M-Gag chimeras were characterized. The N-terminal 74 amino acids of the VSV (Indiana) M protein, including the PPPY motif, was able to replace the L domain of RSV Gag and allow the assembly and release of virus-like particles. Alanine substitutions in the VSV PPPY motif severely compromised the budding activity of this hybrid protein but not that of another chimera which also contained the RSV PPPPY sequence. We conclude that this VSV sequence is functionally homologous to the RSV L domain in promoting virus particle release, making this the first example of such an activity in a virus other than a retrovirus. Both the RSV and VSV motifs have been shown to interact in vitro with certain cellular proteins that contain a WW interaction module, suggesting that the L domains are sites of interaction with unknown host machinery involved in virus release.  (+info)

Site-specific integration mediated by a hybrid adenovirus/adeno-associated virus vector. (3/699)

Adenovirus (Ad) and adeno-associated virus (AAV) have attractive and complementary properties that can be exploited for gene transfer purposes. Ad vectors are probably the most efficient vehicles to deliver foreign genes both in vitro and in vivo. AAV exhibits the unique ability to establish latency by efficiently integrating at a specific locus of human chromosome 19 (AAVS1). Two viral elements are necessary for the integration at AAVS1: Rep68/78 and the inverted terminal repeats (AAV-ITRs). In this study, we report the development of two helper-dependent adenoviral (HD) vectors, one carrying the Rep78 gene, the other an AAV-ITR-flanked transgene. Although Rep proteins have been demonstrated to interfere with Ad replication, HD Rep78 vector was successfully amplified on serial passages in 293CRE4 cells with a yield of 50-100 transducing units per cell. DNA integration at the AAVS1 site also was demonstrated in hepatoma cells coinfected with the HD-expressing Rep78 and with the second HD vector carrying a transgene flanked by AAV-ITRs. The high transduction efficiency, large cloning capacity, and high titer of the HD, combined with the site-specific integration machinery provided by AAV-derived components, make the Ad/AAV hybrid viruses a promising vehicle for gene therapy.  (+info)

Viral burden and disease progression in rhesus monkeys infected with chimeric simian-human immunodeficiency viruses. (4/699)

To determine the role of viral burden in simian-human immunodeficiency virus (SHIV)-induced disease, cellular provirus and plasma viral RNA levels were measured after inoculation of rhesus monkeys with four different SHIVs. These SHIVs included SHIV-HXBc2 and SHIV-89.6, constructed with env, tat, rev, and vpu derived from either cell line-passaged or primary patient isolates of human immunodeficiency virus type 1; the viral quasispecies SHIV-89.6P derived after in vivo passage of SHIV-89.6; and a molecular clone, SHIV-KB9, derived from SHIV-89.6P. SHIV-HXBc2 and SHIV-89.6 are nonpathogenic in rhesus monkeys; SHIV-89.6P and SHIV-KB9 cause rapid CD4(+) T cell depletion and an immunodeficiency syndrome. Relative SHIV provirus levels were highest during primary infection in monkeys infected with SHIV-89.6P, the virus that caused the most rapid and dramatic CD4(+) T cell depletion. However, by 10 weeks postinoculation, provirus levels were similar in monkeys infected with the pathogenic and nonpathogenic chimeric viruses. The virus infections that resulted in the highest peak and chronic viral RNA levels were the pathogenic viruses SHIV-89.6P and SHIV-KB9. SHIV-89. 6P uniformly caused rapid and profound CD4(+) T cell depletion and immunodeficiency. Infection with the SHIV-KB9 resulted in very low CD4(+) T cell counts without seroconversion in some monkeys and a substantial but less profound CD4(+) T cell depletion and rapid seroconversion in others. Surprisingly, the level of plasma viremia did not differ between SHIV-KB9-infected animals exhibiting these contrasting outcomes, suggesting that host factors may play an important role in AIDS virus pathogenesis.  (+info)

Characterization of a neutralization-escape variant of SHIVKU-1, a virus that causes acquired immune deficiency syndrome in pig-tailed macaques. (5/699)

A chimeric simian-human immunodeficiency virus (SHIV-4) containing the tat, rev, vpu, and env genes of HIV type 1 (HIV-1) in a genetic background of SIVmac239 was used to develop an animal model in which a primate lentivirus expressing the HIV-1 envelope glycoprotein caused acquired immune deficiency syndrome (AIDS) in macaques. An SHIV-infected pig-tailed macaque that died from AIDS at 24 weeks postinoculation experienced two waves of viremia: one extending from weeks 2-8 and the second extending from week 18 until death. Virus (SHIVKU-1) isolated during the first wave was neutralized by antibodies appearing at the end of the first viremic phase, but the virus (SHIVKU-1b) isolated during the second viremic phase was not neutralized by these antibodies. Inoculation of SHIVKU-1b into 4 pig-tailed macaques resulted in severe CD4(+) T cell loss by 2 weeks postinoculation, and all 4 macaques died from AIDS at 23-34 weeks postinoculation. Because this virus had a neutralization-resistant phenotype, we sequenced the env gene and compared these sequences with those of the env gene of SHIVKU-1 and parental SHIV-4. With reference to SHIV-4, SHIVKU-1b had 18 and 6 consensus amino acid substitutions in the gp120 and gp41 regions of Env, respectively. These compared with 10 and 3 amino acid substitutions in the gp120 and gp41 regions of SHIVKU-1. Our data suggested that SHIVKU-1 and SHIVKU-1b probably evolved from a common ancestor but that SHIVKU-1b did not evolve from SHIVKU-1. A chimeric virus, SHIVKU-1bMC17, constructed with the consensus env from the SHIVKU-1b on a background of SHIV-4, confirmed that amino acid substitutions in Env were responsible for the neutralization-resistant phenotype. These results are consistent with the hypothesis that neutralizing antibodies induced by SHIVKU-1 in pig-tailed macaque resulted in the selection of a neutralization-resistant virus that was responsible for the second wave of viremia.  (+info)

T cell-tropic simian immunodeficiency virus (SIV) and simian-human immunodeficiency viruses are readily transmitted by vaginal inoculation of rhesus macaques, and Langerhans' cells of the female genital tract are infected with SIV. (6/699)

Intravaginal inoculation with T cell-tropic molecular clones of simian immunodeficiency virus (SIV) or simian-human immunodeficiency virus (SHIV) or some dual-tropic strains of SIV or SHIV produced systemic infection in rhesus macaques. Vaginal inoculation with other dual-tropic molecular clones of SIV or SHIV did not infect rhesus macaques even after multiple inoculations. While in vitro measures of macrophage tropism do not predict which primate lentiviruses will produce systemic infection after intravaginal inoculation, the level to which a virus replicates in vivo after intravenous inoculation does predict the outcome of intravaginal inoculation. Another series of studies, using combined in situ hybridization and immunolabeling to simultaneously detect SIV RNA and identify the immunophenotype of infected cells, demonstrated that a large proportion (approximately 40% in some animals) of the SIV-infected cells in the vagina and cervix were Langerhans' cells. This is the first in vivo demonstration that Langerhans' cells in the genital tract are infected with SIV and that dendritic cells are significant reservoirs for lentiviruses.  (+info)

Distinct pathogenic sequela in rhesus macaques infected with CCR5 or CXCR4 utilizing SHIVs. (7/699)

Infection of macaques with chimeric simian-human immunodeficiency virus (SHIV) provides an excellent in vivo model for examining the influence of envelope on HIV-1 pathogenesis. Infection with a pathogenic CCR5 (R5)-specific enveloped virus, SHIVSF162P, was compared with infection with the CXCR4 (X4)-specific SHIVSF33A.2. Despite comparable levels of viral replication, animals infected with the R5 and X4 SHIV had distinct pathogenic outcomes. SHIVSF162P caused a dramatic loss of CD4+ intestinal T cells followed by a gradual depletion in peripheral CD4+ T cells, whereas infection with SHIVSF33A.2 caused a profound loss in peripheral T cells that was not paralleled in the intestine. These results suggest a critical role of co-receptor utilization in viral pathogenesis and provide a reliable in vivo model for preclinical examination of HIV-1 vaccines and therapeutic agents in the context of the HIV-1 envelope protein.  (+info)

Recombinant viruses expressing the foot-and-mouth disease virus capsid precursor polypeptide (P1) induce cellular but not humoral antiviral immunity and partial protection in pigs. (8/699)

The importance of the induction of virus neutralizing antibodies to provide protection against foot-and-mouth disease virus (FMDV) infection is well established. However, recent studies with recombinant adenovirus expressing the precursor polypeptide of the viral capsid (P1) indicate that cattle inoculated with this recombinant vector developed partial protection against FMDV infection, in the absence of a detectable specific humoral response. Other viral vectors have been widely used to induce protective immunity against many pathogens, and it has been reported that the use of different vectors for priming and boosting injections can provide a synergistic effect on this response. In this work, we determined the immunogenicity of two recombinant viruses (adenovirus and vaccinia) expressing P1-FMDV, administered either individually or sequentially, and the protection that they induced against FMDV challenge in pigs. A double immunization with the adeno-P1 virus was the most effective strategy at inducing protective immunity. In contrast to previous reports, the use of two different vectors for priming and boosting did not show a synergistic effect on the protection induced against FMD. Interestingly, immunized pigs developed FMDV-specific T cell responses but not detectable antibodies. Thus, the protection observed was likely to be mediated by a cellular immune response.  (+info)

If H5N1 viruses acquire the ability to undergo efficient and sustained transmission among humans, a pandemic would be inevitable. An understanding of the molecular and biologic requirements for efficient transmissibility is critical for the early identification of a potential H5N1 pandemic virus and the application of optimal control measures. The results of this study demonstrate, that unlike human H3N2 viruses, avian H5N1 viruses isolated from humans in 1997, 2003, or 2005 lack the ability to transmit efficiently in the ferret model. Furthermore, reassortant viruses bearing 1997 avian H5N1 surface glycoproteins with four or six human virus internal protein genes do not transmit efficiently in ferrets and thus lack the key property that predicts pandemic spread.. We found that the rgVic:486HANA reassortant bearing the H5 HA and human virus M and NS exhibited reduced infectivity for MDCK cells and 10-fold lower viral titers in ferrets compared with rg486:VicRNP that possessed avian virus M and ...
Triple-reassortant swine influenza viruses circulating in North American pigs contain the internal genes derived from swine (matrix, non-structural and nucleoprotein), human [polymerase basic 1 (PB1)] and avian (polymerase acidic and PB2) influenza viruses forming a constellation of genes that is well conserved and is called the triple-reassortant internal gene (TRIG) cassette. In contrast, the external genes [haemagglutinin (HA) and neuraminidase (NA)] are less conserved, reflecting multiple reassortant events that have produced viruses with different combinations of HA and NA genes. This study hypothesized that maintenance of the TRIG cassette confers a selective advantage to the virus. To test this hypothesis, pigs were co-infected with the triple-reassortant H3N2 A/Swine/Texas/4199-2/98 (Tx/98) and the classical H1N1 A/Swine/Iowa/15/1930 viruses and co-housed with a group of sentinel animals. This direct contact group was subsequently moved into contact with a second group of naïve animals. Four
The severity of disease caused in humans by H5N1 influenza viruses remains unexplained. The NS gene of Hong Kong H5N1/97 viruses was shown to contribute to high pathogenicity of reassortants in a pig model. However, the molecular pathogenesis and host immune response underlying this phenomenon remain unclear. Here, in a mouse model, H1N1 A/Puerto Rico/8/34 (PR/8) reassortants that contained the H5N1/97 NS gene, the H5N1/01 NS gene, or an altered H5N1/97 NS gene encoding a Glu92→Asp substitution in NS1 was studied. The pathogenicity of reassortant viruses, the induction of cytokines and chemokine CXCL1 (KC) in the lungs and specific B- and T-cell responses was characterized. In mice infected with reassortant virus containing the H5N1/97 NS gene, the mouse lethal dose (50 %) and lung virus titres were similar to those of PR/8, which is highly pathogenic to mice. This reassortant virus required two more days than PR/8 to be cleared from the lungs of infected mice. Reassortants containing the altered H5N1
The pandemic H1N1 virus of 2009 (2009 H1N1) continues to cause illness worldwide, primarily in younger age groups. To better understand the pathogenesis of these viruses in mammals, we used a mouse model to evaluate the relative virulence of selected 2009 H1N1 viruses and compared them to a representative human triple-reassortant swine influenza virus that has circulated in pigs in the United Stat ...
A reassortant influenza A subtype H1N2 virus with gene segments from seasonal A(H1N1)pdm09 virus (HA, MP, NP, NS, PA, PB1 and PB2) and seasonal A(H3N2) virus (NA) was identified in a routine surveillance sample in Denmark. The patient recovered fully. This is the second reassortant influenza A(H1N2) virus identified in Europe in the 2018/19 influenza season, with the first case being detected December 2018 in Sweden. ...
This serial passaging of the H9N2:pH1N1 reassortant resulted in a virus that replicated in and transmitted between pigs at high rates. The predominant mutation in the passaged reassortant virus was an aspartic acid to glycine at position 225 in the HA RBS. Therefore, our results showed that the combination of reassortment and mutations induced by the serial passages generated a virus with a predominant mutation at position 225 in HA RBS that replicated and transmitted at high rates in pigs. ...
In January 2019, a human seasonal reassortant influenza A(H1N2) virus with a novel 7:1 genetic constellation was identified in a 68-year-old female patient with suspected pneumonia. The virus harboured A(H3N2) neuraminidase and remaining genes from A(H1N1)pdm09. The patient recovered after severe illness. No additional cases have been detected. This is the second identified A(H1N2) seasonal reassortant in a human in Europe within 1 year; a previous case was detected in the Netherlands in March 2018.
Фуф, боялся что нет М. и Б. медведиц, но все таки нашел. Хорошая обоина =) Влад, можете сделать обоину с обычным звездным небом? Ну на фоне может какое-то дерево будет, или скала... очень хочется на рабочий стол звездное небо... Спасибо ...
Caelum, meaning Chisel or Burin is a constellation (albeit one of the more smaller, uninteresting ones) which was de...
H5N1 highly pathogenic avian influenza (HPAI) viruses have seriously affected the Asian poultry industry since their recurrence in 2003. The viruses pose a threat of emergence of a global pandemic influenza through point mutation or reassortment leading to a strain that can effectively transmit among humans. In this study, we present phylogenetic evidences for the interlineage reassortment among H5N1 HPAI viruses isolated from humans, cats, and birds in Indonesia, and identify the potential genetic parents of the reassorted genome segments. Parsimony analyses of viral phylogeography suggest that the reassortant viruses may have originated from greater Jakarta and surroundings, and subsequently spread to other regions in the West Java province. In addition, Bayesian methods were used to elucidate the genetic diversity dynamics of the reassortant strain and one of its genetic parents, which revealed a more rapid initial growth of genetic diversity in the reassortant viruses relative to their genetic
Avian influenza A H5N1 viruses similar to those that infected humans in Hong Kong in 1997 continue to circulate in waterfowl and have reemerged in poultry in the region, raising concerns that these viruses could reappear in humans. The currently licensed trivalent inactivated influenza vaccines contain hemagglutinin (HA) and neuraminidase genes from epidemic strains in a background of internal genes derived from the vaccine donor strain, A/Puerto Rico/8/34 (PR8). Such reassortant candidate vaccine viruses are currently not licensed for the prevention of human infections by H5N1 influenza viruses. A transfectant H5N1/PR8 virus was generated by plasmid-based reverse genetics. The removal of the multibasic amino acid motif in the HA gene associated with high pathogenicity in chickens, and the new genotype of the H5N1/PR8 transfectant virus, attenuated the virus for chickens and mice without altering the antigenicity of the HA. A Formalin-inactivated vaccine prepared from this virus was immunogenic and
Following the emergence of swine influenza A(H3N2) variant (v) viruses with sporadic human infections in North America, the Community Network of Reference Laboratories (CNRL) and the Animal Health and Veterinary Laboratories Agency completed an exercise to assess the CNRLs capability to detect novel reassortant and circulating triple reassortant swine viruses (TRA) in humans. ...
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Prior research developed Reassortment Networks to reconstruct the evolution of segmented viruses under both reassortment and mutation. We report their appl
Emergence of influenza viruses from the animal reservoir is a permanent challenge. The rapid description and immediate sharing of information on these viruses is invaluable for influenza surveillance networks and for pandemic preparedness. With the help of data generated from the World Health Organization Collaborating Centre for Reference and Research on Influenza at the United States Centers for Disease Control and Prevention*, we provide here information on the swine-origin triple reassortant influenza A(H3N2) viruses detected in human cases in the north-east of the United States. .
Over 22 years ago, the August 1995 issue of the Journal of Virology published a study very similar to the one being discussed today called Selection of a Single Amino Acid Substitution in the Hemagglutinin Molecule by Chicken Eggs Can Render Influenza A Virus (H3) Candidate Vaccine Ineffective. The study essentially concluded that thanks to mutations, (which are extremely common), growing these viruses in mutated eggs should be ended. Thus, it is recommended that in the selection of vaccine candidates, virus populations with the egg-adapted HA Lys-156 substitution be eliminated. Yes, I realize that this is a bit different mutation than the one we were discussing earlier, but the principles are the same. Said mutations caused a vaccine that was described with words such as nonprotective, poorly recognized, and that, egg-grown HA Lys-156 variant induced an AFC profile vastly different from that elicited by the other two reassortant vaccines. With this being the case, why should be be ...
In the last several years, public health officials have been monitoring two varieties of bird flu viruses with alarming properties: H7N9 and H5N8. Scientists at Emory have been probing the factors that limit reassortment between these strains and a well-known strain (H3N2) that has been dominating the last few flu seasons in the United States.. Helen Branswell has an article in STAT this week, explaining that H5N8 actually emerged from reassortment involving much-feared-but-not-damaging-to-humans-so-far H5N1:. Several years ago, these viruses effectively splintered, with some dumping their N1 neuraminidase - a gene that produces a key protein found on the surface of flu viruses - and replacing it with another. The process is called reassortment, and, in this case, it resulted in the emergence of a lot of new pairings over a fairly short period of time.. The most common and most dangerous viruses to emerge - for birds at least - have been H5N6 and H5N8 viruses. Both are highly pathogenic, meaning ...
Reassortment contributes to the evolution of RNA viruses with segmented genomes, including Bluetongue virus (BTV). Recently, co-circulation of natural and vaccine BTV variants in Europe, and their ensuing reassortment, were proposed to promote appearance of novel European BTV strains, with potential implications for pathogenicity, spread and vaccination policies. Similarly, the geographical features of the Mediterranean basin, which spans over portions of three continents, may facilitate the appearance of clinically relevant reassortants via co-circulation of BTV strains of African, Asian and European origins. In August–October 2017, BTV serotype 6 (BTV-6) was identified in young animals exhibiting classical clinical signs of Bluetongue (BT) at Israeli sheep and cattle farms. Sequencing and pairwise analysis of this Israeli BTV-6 isolate revealed the closest sequence homology of its serotype-defining Segment 2 was with that of South African reference BTV-6 strain 5011 (93.88% identity). In
Read Isolation and genetic characterization of novel reassortant H6N6 subtype avian influenza viruses isolated from chickens in eastern China, Archives of Virology on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Description: FluMist is prepared as a live, attenuated trivalent vaccine for administration by intranasal spray. The influenza virus strains in FluMist are cold-adapted which means that they grow efficiently at 25°C and restricted growth at temperatures of 37°-39°C. Specific pathogen-free (SPF) eggs are inoculated with each of the reassortant strains and incubated to allow vaccine virus replication. The allantoic fluid of these eggs is harvested, pooled and then clarified by filtration. Each pre-filled refrigerated FluMist sprayer contains a single 0.2 mL dose. Each 0.2 mL dose contains 10^6.5-7.5 FFU of live attenuated influenza virus reassortants of each of the three strains: A/California/7/2009 (H1N1), A/Perth/16/2009 (H3N2), and B/Brisbane/60/2008. Each 0.2 mL dose also contains 0.188 mg/dose monosodium glutamate, 2.00 mg/dose hydrolyzed porcine gelatin, 2.42 mg/dose arginine, 13.68 mg/dose sucrose, 2.26 mg/dose dibasic potassium phosphate, 0.96 mg/dose monobasic potassium phosphate, and ...
Since emergence of the pandemic (H1N1) 2009 virus in April 2009, three influenza A viruses-seasonal (H3N2), seasonal (H1N1), and pandemic (H1N1) 2009-have circulated in humans. Genetic reassortment between these viruses could result in enhanced pathogenicity. We compared 4 reassortant viruses with favorable in vitro replication properties with the wild-type pandemic (H1N1) 2009 virus with respect to replication kinetics in vitro and pathogenicity and transmission in ferrets. Pandemic (H1N1) 2009 viruses containing basic polymerase 2 alone or in combination with acidic polymerase of seasonal (H1N1) virus were attenuated in ferrets. In contrast, pandemic (H1N1) 2009 with neuraminidase of seasonal (H3N2) virus resulted in increased virus replication and more severe pulmonary lesions. The data show that pandemic (H1N1) 2009 virus has the potential to reassort with seasonal influenza viruses, which may result in increased pathogenicity while it maintains the capacity of transmission through aerosols or
Read Evolution of DS-1-like G1P[8] double-gene reassortant rotavirus A strains causing gastroenteritis in children in Vietnam in 2012/2013, Archives of Virology on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
This researcher is very confident that a focused criminal investigation would likely reveal prima facia evidence that Taubenberger was in reality working for Novartis while employed with the N.I.H. and was quite likely the primary author of Novartis Nov. 6, 2005 provisional patent application. On page 2, paragraph 32 of the patent publication we read, quote: The influenza virus [that the invention vaccine is designed to protect against] may be a reassortant strain, and may have been obtained by reverse genetics techniques. Reverse genetics techniques allow influenza viruses with desired genome segments to be prepared in vitro using plasmids. The remnant of the paragraph then goes into very specific detail as to the actual mechanics of how the pandemic virus was actually created by Taubenbergers Ft. Detrick team. At the very least, the author of the patent application had to have studied Taubenbergers various published reports on his work at Detrick, for the wording and science is ...
Genetic exchange by a process of genome-segment reassortment represents an important mechanism for evolutionary change in all viruses with segmented genomes, yet in many cases a detailed understanding of its frequency and biological consequences is lacking. We provide a comprehensive assessment of reassortment in bluetongue virus (BTV), a globally important insect-borne pathogen of livestock, during recent outbreaks in Europe. Full-genome sequences were generated and analysed for over 150 isolates belonging to the different BTV serotypes that have emerged in the region over the last 5 decades. Based on this novel dataset we confirm that reassortment is a frequent process that plays an important and on-going role in evolution of the virus. We found evidence for reassortment in all ten segments without a significant bias towards any particular segment. However, we observed biases in the relative frequency at which particular segments were associated with each other during reassortment. This ...
In 2016, a novel HPAI A(H5N8) virus clade emerged and spread to Russia, Europe, and Africa. We demonstrated that several internal genes from viruses in ducks in Bangladesh have an equivalent or higher consensus identity to those of other viruses of wild birds in central Asia, suggesting that these viruses could be gene donors to the novel reassortant A(H5N8) viruses, which were then disseminated by wild birds. The novel HPAI A(H5N8) viruses diverged along 2 genotypes with independent origins of reassortment for several gene segments. The HA, NA, and NS genes were related to group B of H5N8 clade viruses that circulated in China from 2013. Group B is still circulating in China, and a previous study showed that these viruses had PB2 and NS genes derived from domestic ducks in eastern China (13), indicating further reassortment events.. The route of spread of HPAI A(H5N1) viruses from eastern Asia to Europe, Africa, and the Middle East in 2005 and 2006 most likely occurred by ...
To elucidate the molecular basis of the virulence discrepancy between the HK483 and HK486 viruses, we generated a spectrum of single-gene reassortants (Fig. 1) and tested their pathogenicity in mice. Among nine single-gene reassortant viruses, each containing one gene segment from HK486 virus and the remaining segments from HK483 virus, only those possessing the PB2 (HK3/6PB2) or HA-227I (HK3/6HA227I) gene from the HK486 virus were appreciably attenuated (MLD50, 1.0 × 104 or 1.1 × 102PFU, respectively, compared with ,5 PFU for all other transfectants) (Fig. 1). Moreover, although more than 106 PFU/g of virus was detected at 6 days after infection in the lungs of mice infected with either HK3/6PB2 or HK3/6HA227I virus (Table 1), virus was not recovered from other nonrespiratory organs (with the exception of the heart in mice infected with HK3/6PB2 virus). By contrast, the single-gene reassortants containing the HK486HA227S (HK3/6HA227S) gene or the HK486 NA (HK3/6NA) gene (both tested as ...
On 31 March 2013, the Chinese authorities announced the identification of a novel influenza A virus, A(H7N9), in three seriously ill people from two provinces presenting with respiratory infections. So far, no epidemiological link has been identified between those three patients. When testing for the influenza virus, the Chinese Center for Disease Control and Prevention identified genes from both A(H7N9) and A(H9N2) viruses, thus indicating a novel reassortant avian influenza A virus. In its initial assessment of the situation, the ECDC rapid risk assessment concludes that the risk of the spread of the virus in Europe can be considered low at this stage ...
Researchers from UCLAs Institute of the Environment and Sustainability Center for Tropical Research have developed a technique to predict areas where viruses might reassort and generate a future pandemic.
No, I dont think you cant say the the development of cecal valves could only occur with an increase in the amount of genetic material. Remember that these lizards are descended from a total of 10 original lizards. So, any particular gene locus could have been present in multiple different versions (alleles) in the founding population. As the population expanded, those alleles would have reassorted into many combinations that werent present in any single founding lizard. In addition, most traits are influenced by combinations of lots of genes and loci. So the appearance of cecal valves might not involve any new mutations. It might just involve new combinations of alleles that already existed individually in the founding population ...
Hmm...what if instead of moving 1 square after every players turn, the constellation went on the DMs turn and moved 1d10 squares (or possibly at initiative count 10 and 0, and moved 1d6 squares)? That way youd need to keep running, but there would be an element of luck & risk/reward. If I move to this square 6 spaces away from the constellation I can attack 2 people, but if I move to the square 8 squares away from the constellation I can only attack 1. Is it worth it?. ReplyDelete ...
The complete nucleotide sequences of the small (S) and medium (M) segments of three independent strains of Crimean-Congo haemorrhagic fever (CCHF) virus isolated in Uzbekistan, Iraq and Pakistan have been determined. Partial S and M segment sequences from two additional strains and partial large segment sequences from five strains of CCHF virus have also been obtained. These data have been compiled and compared with published full-length and partial sequences of other CCHF virus strains. Analysis of virus strains for which complete and partial S and M segment sequences are available reveals that the phylogenetic grouping of some strains differ between these two segments. Data provided in this report suggest that this discrepancy is not the result of recombination, but rather the consequence of reassortment events that have occurred in some virus lineages. Although described in other genera of the Bunyaviridae family, this is the first report of segment reassortment occurring in the Nairovirus genus.
Eight new full-length sequences from highly pathogenic avian influenza viruses (H5N1) from 4 states in southwest Nigeria were analyzed. All gene sequences were more closely related to the first strains found in Nigeria in 2006 than to any strain found outside the country. Six viruses had evolved by at least 3 reassortment events (AC HA/NS, AC NS) from previously identified sublineages A (EMA 2) and C (EMA 1). Our results suggest that highly pathogenic avian influenza viruses (H5N1) initially imported into Nigeria in 2006 have been gradually replaced by various reassortments. In all reassortants, nonstructural genes were derived from sublineage C with 2 characteristic amino acids (compared with sublineage A). If the high prevalence of reassortants was typical for West Africa in 2007, the absence of such reassortants anywhere else suggests that reintroductions of influenza A (H5N1) from Africa into Eurasia must be rare ...
This vaccine was efficacious in preventing rotavirus gastroenteritis, decreasing severe disease and health care contacts. The risk of intussusception was similar in vaccine and placebo recipients. ( number, NCT00090233.)
Human infections with Eurasian avian-like swine influenza H1N1 viruses have been reported in China in past years. One case resulted in death and others were mild case. In 2016, the World Health Organization recommended the use of A/Hunan/42443/2015(H1N1) virus to construct the first candidate vaccine strain for Eurasian avian-like swine influenza H1N1 viruses. Previous reports showed that the neuraminidase of A/Puerto Rico/8/34(H1N1) might improve the viral yield of reassortant viruses. Therefore, we constructed two reassortant candidate vaccine viruses of A/Hunan/42443/2015(H1N1) by reverse genetic technology, with (6+2) and (7+1) gene constitution, respectively. The (6+2) virus had hemagglutinin and neuraminidase from A/Hunan/42443/2015, and the (7+1) one had hemagglutinin from A/Hunan/42443/2015, while all the other genes were from A/Puerto Rico/8/34. Our data revealed that although the neuraminidase of the (7+1) virus was from high yield A/Puerto Rico/8/34, the hemagglutination titer and the ...
Influenza Vaccine Reduces Risk of Adverse Cardiovascular Events in High-Risk Patients [POEMs] This meta-analysis found that the influenza vaccine is associated with a significantly lower risk of major adverse cardiovascular events in adults with coronary disease. The benefit of influenza vaccination is strongest in adults with a history of recent acute coronary syndrome within the previous six months (number needed to treat [NNT] = 8).. ...
131716PRTInfluenza A virus 1Met Glu Asp Phe Val Arg Gln Cys Phe Asn Pro Met Ile Val Glu Leu1 5 10 15Ala Glu Lys Thr Met Lys Glu Tyr Gly Glu Asp Leu Lys Ile Glu Thr 20 25 30Asn Lys Phe Ala Ala Ile Cys Thr His Leu Glu Val Cys Phe Met Tyr 35 40 45Ser Asp Phe His Phe Ile Asn Glu Gln Gly Glu Ser Ile Ile Val Glu 50 55 60Leu Gly Asp Pro Asn Ala Leu Leu Lys His Arg Phe Glu Ile Ile Glu65 70 75 80Gly Arg Asp Arg Thr Met Ala Trp Thr Val Val Asn Ser Ile Cys Asn 85 90 95Thr Thr Gly Ala Glu Lys Pro Lys Phe Leu Pro Asp Leu Tyr Asp Tyr 100 105 110Lys Glu Asn Arg Phe Ile Glu Ile Gly Val Thr Arg Arg Glu Val His 115 120 125Ile Tyr Tyr Leu Glu Lys Ala Asn Lys Ile Lys Ser Glu Lys Thr His 130 135 140Ile His Ile Phe Ser Phe Thr Gly Glu Glu Met Ala Thr Lys Ala Asp145 150 155 160Tyr Thr Leu Asp Glu Glu Ser Arg Ala Arg Ile Lys Thr Arg Leu Phe 165 170 175Thr Ile Arg Gln Glu Met Ala Ser Arg Gly Leu Trp Asp Ser Phe Arg 180 185 190Gln Ser Glu Arg Gly Glu Glu Thr Ile Glu Glu Arg Phe Glu Ile Thr 195 200 205Gly Thr Met Arg Lys ...
darcoda at (S. Frog) wrote: , , , Hi, and all that. , , Im not sure if this is the proper place to raise this question, , and forgive me if it isnt, but I have a question about the flu. , Actually, three questions: , Is the flu a retrovirus? , If it isnt a retrovirus, do I have a faulty definition of what a , retrovirus is? , Lastly, is it true that the flu has only been around for like a , hunred years or so? And that it mutated from something else, which is , why human has so little resistence to it when the influenza epidemic , roared through just after world war I? , , , Thanks. :) , , , , , S. Frog , -- , , , .. The agent which causes many cases of the flu is called influenza. It is a member of the Orthomyxoviridae. These viruses have a segmented, single stranded RNA genome. Their segmented genome enables them to undergo a special kind of mutation (actually it is segment reassortment) called antigenic shift, which causes the pandemics in human medicine. Many species ...
Thanks to Greg Folkers for sending the link to this February 13 rapid communication in Eurosurveillance: Possible pandemic threat from new reassortment of influenza A(H7N9) virus in China. Rather than provide the brief abstract, heres the discussion: Our analysis revealed...
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General Info. The best way to prevent illness from COVID-19 is to avoid being exposed to the virus, as there is currently no vaccine to prevent the disease.. The virus spreads mainly through person-to-person contact, when individuals are within about 6 feet of each other. When an infected person cough, sneezes or talks, it produces respiratory droplets. These droplets can be inhaled by nearby individuals, leading to an infection. The infected person may be asymptomatic at the time they are spreading the infection to others.. It is also possible for a person to get COVID-19 when they touch a surface or object which has recently been contaminated by respiratory droplets from infected individuals, and then touch their eyes, mouth or nose. The virus can live for many hours or days on such surfaces.. For this reason, it is safest to assume that every individual is potentially infected with COVID-19, and can spread it to others. All individuals on campus must be instructed to follow these general ...
Generally speaking, viruses and germs can spread from person to person through the air or by touching things that have been infected.. Germs that are spread through the air are the most potent because they have just been launched from the person carrying the infection.. This is why personal contact with an infected person - such as a handshake or breathing in droplets from a cough or sneeze - is the most common way these viruses spread.. In many cases, germs are most infectious before the carrier even has any symptoms. If symptoms are not present, respiratory droplets carrying the disease can fly through the air to about six feet and land on another person.. Coughing spreads infected respiratory droplets as far as six meters, and sneezing as much as eight meters. While these droplets stay suspended in the air for up to 10 minutes it is unknown how long the air inside a room occupied by someone with a virus remains potentially infectious.. If there is no one around to catch the germs, they land ...
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This virus was originally referred to as swine flu because laboratory testing showed that many of the genes in this new virus were very similar to influenza viruses that normally occur in pigs (swine) in North America. But further study has shown that this new virus is very different from what normally circulates in North American pigs. It has two genes from flu viruses that normally circulate in pigs in Europe and Asia and bird (avian) genes and human genes. Scientists call this a quadruple reassortant virus. ...
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Messier 3 NGC 5272 Constellation: Canes Venatici Right Ascension: 13h42.2m Declination: +28°23 Magnitude: 6.2 Diameter: 16.2 Distance: ~33,900...
TY - JOUR. T1 - Genetic reassortment of bluetongue virus Serotype 11 strains in the bovine. AU - Oberst, R. D.. AU - Stott, Jeffrey L. AU - Blanchard, Myra. AU - Osburn, Bennie. PY - 1987. Y1 - 1987. N2 - Reassortants of bluetongue virus Serotype 11 (BTV-11) were isolated from a yearling heifer experimentally infected with two electrophoretically different strains (UC-2 and UC-8) by subcutaneous inoculation. Viruses were recovered by direct titration of sonicated blood samples onto Vero cell monolayers, which were overlaid with agarose and later plaque purified. The parental electropherotype of UC-8 was identified as the predominant virus strain during the infection; UC-2 was not isolated. UC-2 inffectivity was shown by reassortants which contained genome segments that were identical in migration pattern to the parental UC-2 electropherotype. The observations demonstrate that segmental reassortment can occur during mixed infections in the bovine, between strains of the same BTV serotype.. AB - ...
Rotavirus, the most common diarrheal pathogen in children worldwide, causes approximately one third of diarrhea-associated hospitalizations and 800,000 deaths per year. Because natural infection reduces the incidence and severity of subsequent episodes, rotavirus diarrhea might be controlled through vaccination. Serotype-specific immunity may play a role in protection from disease. Tetravalent rhesus-human reassortant rotavirus vaccine (RRV-TV) (which contains a rhesus rotavirus with serotype G3 specificity and reassortant rhesus-human rotaviruses with G1, G2, and G4 specificity) provides coverage against the four common serotypes of human rotavirus. In clinical trials in industrialized countries, RRV-TV conferred 49% to 68% protection against any rotavirus diarrhea and 61% to 100% protection against severe disease. This vaccine was licensed by the U.S. Food and Drug Administration on August 31, 1998, and should be cost-effective in reducing diarrheal diseases in industrialized countries. The vaccine&
The use of monoclonal antibodies Fab28 and Fab49 for the prophylactic or therapeutic treatment of swine-origin influenza A (H1N1) virus (S-OIV) infections is described, the which virus is responsible for the influenza syndrome commonly known as
Differential expression profile of microRNAs in human placentas from preeclamptic pregnancies vs normal pregnancies. Explanations of these effects buy meldonium online no prescription and their implications on research on IAMs are discussed. Inseeing thatmation regarding HPV seroprevalence among MSM in Brazil is limited, and a meldonium cheap online greater knowledge of HPV seroprevalence is needed to develop recommendations quest of use of a HPV vaccine. We discuss the significance of our findings to infectious disease transmission within healthcare settings in general as well as specifically to the epidemiology of CDI. In both these years influenza viruses emerged that displayed certain characteristics of pandemic viruses, including unusually high morbidity and mortality impact, but which did not acquire new gene segments through reassortment with other influenza virus subtypes. Funding Statement The present investigation was supported around a bountiful grant from the Danish Council as a ...
The CXB set of recombinant inbred mouse strains provided an opportunity to observe the effects of reassorted subsets of genes on the shape of the mandible. The distances between 12 landmarks in all paired combinations were calculated to evaluate genetic control in small regions. The genetic relationships between interlandmark distances revealed genes to have most of their effects in localized regions, and the greater heritabilities usually to apply to those distances between adjacent landmarks. Interrelationships between measurements are usually explicable on a developmental basis. It is proposed that genes of this sort bring about the changes seen in organ shape during evolution. A model plan for the organization of gene activation during morphogenesis is described.
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I was introduced to the Systemic Constellation Work by a very dear friend. I went to the Family Constellation Workshop with an open mind to create mental health in my family as my two sons were diagnosed with Schizophrenia and my brother had been diagnosed with this illness more than 25 years ago. Under Kristas expert guidance in the Constellation process we worked through the pain and suffering my ancestors had experienced in WWII. Shortly after the workshop things started changing with my children and my brother. Today, three years later, both of my sons are doing very well, attending college and are fairly well adjusted. One of them has not taken medications for over two years. My brother has been communicating with us for approximately two years now as he has been willing to take medication. My brother tells he had gone on a long 25 year trip somewhere and is now back. I am so grateful that I was introduced to this amazing work. Thank you Krista for your gift in facilitating, and giving me ...
To prevent getting and spreading COVID-19, make sure you practice good personal health habits and avoid being exposed to the virus. Wear a face covering to stop the spread of COVID-19 Wisconsin has significant community spread, and the science shows that wearing a face covering can prevent the transmission of the respiratory droplets that spread COVID-19. Protect your loved
If a respiratory droplet from a person infected with COVID-19 lands on a surface, it becomes a possible source of disease spread. This is known as the fomite ro
Some anti-maskers who previously refused to wear facial coverings are apparently deciding to wear face masks that offer no actual protection from respiratory droplets that can help spread a virus the COVID-19.
As of 2004, H3N2 virus isolates in US swine and turkey stocks were triple reassortants, containing genes from human (HA, NA, ... Swine influenza virus (SIV) or swine-origin influenza virus (S-OIV) is any strain of the influenza family of viruses that is ... G4 EA H1N1, also known as the G4 swine flu virus (G4) is a swine influenza virus strain discovered in China. The virus is a ... A triple reassortment event in a pig host of North American H1N1 swine virus, the human H3N2 virus and avian H1N1 virus ...
"Macaque Proteome Response to Highly Pathogenic Avian Influenza and 1918 Reassortant Influenza Virus Infections". Journal of ... Rhesus macaques, like many macaques, carry the herpes B virus. This virus does not typically harm the monkey, but is very ... Bragg, Rick (1997-12-14) "A Drop of Virus From a Monkey Kills a Researcher in 6 Weeks". New York Times "Yerkes 'family' pulled ... Both viruses stimulated innate immune system inflammation, but the 1918 flu stimulated stronger and more persistent ...
... flu strains were caused by reassortment between an avian virus and a human virus. In addition, the H1N1 virus responsible for ... The new reassortant strain will share properties of both of its parental lineages. Reassortment is responsible for some of the ... Studies on host-virus interactions in the chick embryo-influenza virus system. VI. Evidence for multiplicity reactivation of ... The multiplication of influenza virus. II. Multiplicity reactivation of ultraviolet irradiated virus. Virology. 1961 Aug;14:398 ...
Among the many viruses and fevers that [Kenneth Smithburn] researched are [...] Bwamba Fever Virus (1939-1943)' Lutwama, J. J ... 2001). "A reassortant bunyavirus isolated from acute hemorrhagic fever cases in Kenya and Somalia". Virology. 291 (2): 185-190 ... where the virus was initially discovered. The distribution of the virus tends to be underestimated because the symptoms are ... Bwamba fever is present in large parts of Africa and antibodies of the virus have been found 'as far south as the Republic of ...
"Bunyamwera virus (BUNV)". Gerrard SR, Li L, Barrett AD, Nichol ST (2004). "Ngari virus is a Bunyamwera virus reassortant that ... Reassortant viruses derived from Bunyamwera orthobunyavirus, such as Ngari virus, have been associated with large outbreaks of ... The N protein is the most abundant protein in virus particles and infected cells and, therefore, the main target in many ... Briese, T.; Bird, B.; Kapoor, V.; Nichol, S. T.; Lipkin, W. I. (12 May 2006). "Batai and Ngari Viruses: M Segment Reassortment ...
"Experimental adaptation of an influenza H5 HA confers respiratory droplet transmission to a reassortant H5 HA/H1N1 virus in ... In 2012, the NIHE provided the H5N1 bird flu virus to researchers who transformed it and used the product to infect ferrets. On ...
"Experimental adaptation of an influenza H5 HA confers respiratory droplet transmission to a reassortant H5 HA/H1N1 virus in ... "H5N1 Hybrid Viruses Bearing 2009/H1N1 Virus Genes Transmit in Guinea Pigs by Respiratory Droplet". Science. 340 (6139): 1459- ... In vaccine development, gain-of-function research is conducted to gain a head start on a virus and to develop a vaccine or ... It is of no use for vaccine development and the benefit in terms of surveillance for new flu viruses is oversold," while Lord ...
"Experimental adaptation of an influenza H5 HA confers respiratory droplet transmission to a reassortant H5 HA/H1N1 virus in ... A group of Australian researchers unintentionally changed characteristics of the mousepox virus while trying to develop a virus ... These viruses seem to overcome an obstacle which limits the global impact of natural H5N1. In 2012, scientists further screened ... The modified virus became highly lethal even in vaccinated and naturally resistant mice. In 2011, two laboratories published ...
The fifth reassortant virus expresses the attachment protein VP4, (type P1A), from the human rotavirus parent strain and the ... The rotavirus A parent strains of the reassortants were isolated from human and bovine hosts. Four reassortant rotaviruses ... It contain human bovine reassortant strains of rotavirus serotypes G1, G2, G3, G4 and G9. This is world's first thermostable ... Rotavirus antigens for parenteral delivery, such as the P2-VP8 candidate, can be expressed as virus-like particles prepared in ...
"Macaque Proteome Response to Highly Pathogenic Avian Influenza and 1918 Reassortant Influenza Virus Infections". J Virol 84 (22 ... Os macacos rhesus, como moitos outros macacos, portan o virus herpes B. Este virus non lle causa danos ao mono normalmente, ... A Drop of Virus From a Monkey Kills a Researcher in 6 Weeks, By RICK BRAGG, New York Times, December 14, 1997 ... Ambos os virus estimulaban a inflamación do sistema inmunitario innato, pero o de 1918 estimulaba unha inflamación máis forte e ...
In Phase 3, an animal or human-animal influenza reassortant virus has caused sporadic cases or small clusters of disease in ... Even though such viruses might theoretically develop into pandemic viruses, in Phase 1 no viruses circulating among animals ... clade 2 is the virus isolated in Indonesia. Vaccine research has mostly been focused on clade 1 viruses, but the clade 2 virus ... The avian flu virus H5N1 has the potential to mutate into a pandemic strain, but so do other types of flu virus. Once a ...
... either by direct transmission of the virus or by contributing one or several RNA segments to reassortants with human strains. ... As with influenza virus, a dual classification system is used based on two proteins on the surface of the virus. The ... In the intervening years, a virus in mice was shown to be related to the virus causing scours. In 1973, Ruth Bishop and ... In 1976, related viruses were described in several other species of animals. These viruses, all causing acute gastroenteritis, ...
... either by direct transmission of the virus or by contributing one or several RNA segments to reassortants with human strains. ... As with influenza virus, a dual classification system is used based on two proteins on the surface of the virus. The ... VP4 determines how virulent the virus is and it determines the P-type of the virus. In humans there is an association between ... In the intervening years, a virus in mice was shown to be related to the virus causing scours. In 1973, Ruth Bishop and ...
... when most other isolates were reassortants." In January 2004, the predominant flu virus circulating in humans in Europe was ... viruses, three influenza A (H1) viruses, one influenza A (H7N2) virus, and 71 influenza B viruses. Of the 949 influenza A (H3N2 ... The "H5N1 viruses from human infections and the closely related avian viruses isolated in 2004 and 2005 belong to a single ... "Many experts who follow the ongoing analysis of the H5N1 virus sequences are alarmed at how fast the virus is evolving into an ...
"Macaque Proteome Response to Highly Pathogenic Avian Influenza and 1918 Reassortant Influenza Virus Infections". Journal of ... "Lethal Influenza Virus Infection in Macaques Is Associated with Early Dysregulation of Inflammatory Related Genes". PLoS ...
"Interspecies and intraspecies transmission of triple reassortant H3N2 influenza A viruses". Virol J. 28 (4): 129. doi:10.1186/ ... Influenza B and C viruses are almost exclusively isolated from man, although influenza C virus has also been isolated from pigs ... International Committee on Taxonomy of Viruses. "The Universal Virus Database, version 4: Influenza A".. ... "Virus Res. 48 (1): 71-9. PMID 9140195.. CS1 maint: Explicit use of et al. (link) CS1 maint: Multiple names: authors list (link) ...
The frequent reassortment and cocirculation of the genetically distinct reassortant viruses in a community". J. Med. Virol. 74 ... Influenza B virus is the only species in the genus Betainfluenzavirus in the virus family Orthomyxoviridae. Influenza B virus ... Further diminishing the impact of this virus, "in humans, influenza B viruses evolve slower than A viruses and faster than C ... The subtypes of influenza A virus are estimated to have diverged 2,000 years ago. Influenza viruses A and B are estimated to ...
EHDV-6 is thought to be a hybrid form where each of the collected type-6 viruses were all reassortants containing VP2 and VP5 ... other orbiviruses include equine encephalosis virus and African horse sickness virus. Epizootic hemorrhagic disease virus's ... "Detection of a novel reassortant epizootic hemorrhagic disease virus (EHDV) in the USA containing RNA segments derived from ... VP6 and VP7 of epizootic haemorrhagic disease virus (EHDV)". Virus Research. 145 (2): 187-99. doi:10.1016/j.virusres.2009.07. ...
Most H3N2 virus isolates are triple reassortants, containing genes from human (HA, NA, and PB1), swine (NS, NP, and M), and ... Influenza A virus subtype H3N2 (A/H3N2) is a subtype of viruses that causes influenza (flu). H3N2 viruses can infect birds and ... like virus an A/Brisbane/10/2007 (H3N2)-like virus a B/Florida/4/2006-like virus (B/Florida/4/2006 and B/Brisbane/3/2007 (a B/ ... like virus an A/Victoria/210/2009 (an A/Perth/16/2009-like strain) (H3N2)-like virus a B/Brisbane/60/2008-like virus The ...
2018). "Case of seasonal reassortant A(H1N2) influenza virus infection, the Netherlands, March 2018". Euro Surveill. 23 (15). ... Influenza A virus subtype H1N2 (A/H1N2) is a subtype of the species Influenza A virus (sometimes called bird flu virus). It is ... The virus does not cause more severe illness than other influenza viruses, and no unusual increases in influenza activity have ... Because the hemagglutinin protein of the virus is similar to that of the currently[when?] circulating A(H1N1) viruses and the ...
According to research published by the US National Institutes of Health, the triple reassortant H2N3 virus isolated from ... the swine H2N3 virus was more pathogenic causing severe pneumonia in nonhuman primates. Both viruses replicated in the entire ... H2N3 is a subtype of the influenza A virus. Its name derives from the forms of the two kinds of proteins on the surface of its ... Swine H2N3 virus was also detected to significantly higher titers in nasal and oral swabs indicating the potential for animal- ...
... recombinants and reassortants of severe fever with thrombocytopenia syndrome virus. Ticks Tick Borne Dis. 2017 Mar;8(3):385-390 ... California encephalitis virus, La Crosse encephalitis virus, Jamestown Canyon virus and Snowshoe hare virus vector: mosquitoes ... "Bunyaviridae - Negative Sense RNA Viruses - Negative Sense RNA Viruses (2011)". International Committee on Taxonomy of Viruses ... Viruses. 12 (9): 1010. doi:10.3390/v12091010. Virus Taxonomy: 2018 Release, International Committee on Taxonomy of Viruses, ...
In Phase 3, an animal or human-animal influenza reassortant virus has caused sporadic cases or small clusters of disease in ... The 1977 virus was similar to other A/H1N1 viruses that had circulated prior to 1957. The virus was included in the 1978-79 ... Even though such viruses might theoretically develop into pandemic viruses, in Phase 1 no viruses circulating among animals ... Physical characteristics of influenza A viruses. UMN CIDRAP.. *^ "Flu viruses 'can live for decades' on ice". The New Zealand ...
... respiratory syncytial virus and influenza vaccines. She has worked extensively with American Indian populations and in Africa ... Reassortant Rotavirus Vaccine". New England Journal of Medicine. 354 (1): 23-33. doi:10.1056/NEJMOA052664. PMID 16394299. ... "Global burden of acute lower respiratory infections due to respiratory syncytial virus in young children: a systematic review ...
Gerrard, Sonja R.; Li, Li; Barrett, Alan D.; Nichol, Stuart T. (2004-08-15). "Ngari Virus Is a Bunyamwera Virus Reassortant ... Omsk Hemorrhagic Fever virus, Alkhurma virus, Kyasanur Forest virus (reclassified from B to C) Powassan virus (Deer Tick virus ... Nipah virus Rabies SARS coronavirus Tick-borne encephalitis virus Tick-borne hemorrhagic fever viruses Other hantaviruses Other ... Junin virus, Machupo virus, Guanarito virus, Lassa fever Bunyaviruses: Hantaviruses, Rift Valley Fever, Crimean-Congo ...
Some diseases that occur as a result of this virus or are associated with this virus include mild upper respiratory illness, ... "Genetic and pathogenic characterization of a novel reassortant mammalian orthoreovirus 3 (MRV3) from a diarrheic piglet and ... the virus is brought into the cell via receptor-mediated endocytosis. Following the internalization of the virus, the viral ... from respiratory enteric orphan virus. The Mammalian orthoreovirus was labeled an orphan virus in the 1950s when it was ...
Most H3N2 virus isolates are triple reassortants, containing genes from human (HA, NA, and PB1), swine (NS, NP, and M), and ... Influenza A virus subtype H3N2 (A/H3N2) is a subtype of viruses that causes influenza (flu). H3N2 viruses can infect birds and ... a B/Florida/4/2006-like virus (B/Florida/4/2006 and B/Brisbane/3/2007 (a B/Florida/4/2006-like virus) were used at the time)[20 ... B/Massachusetts/2/2012-like virus,[30]. Quadrivalent vaccines include a B/Brisbane/60/2008-like virus.[31] The CDC announced ...
... whereas reassortant viruses were incubated at 37°C for 48 h. All research with H5N1 viruses or reassortant viruses was ... Plasmids and Rescue of Reassortant Viruses.. Plasmid-based rg was used to generate the reassortant viruses used in this study. ... Characterization of Avian-Human Reassortant Influenza Viruses.. To evaluate the pandemic potential of H5N1 reassortant viruses ... reassortant viruses containing various gene constellations from the avian H5N1 virus, HK486, and the human H3N2 virus, Vic75, ...
... Hagag, Naglaa M. Anim Hlth Res Inst, ... The virus was derived as a result of genetic reassortment between avian influenza viruses of H5N8 and H9N2 subtypes circulating ... Viruses On the subject. Microbiology Search outside of DiVA. GoogleGoogle Scholar. ... In this study, the HPAI (H5N2) virus was isolated from a commercial duck farm, giving evidence of the emergence of the first ...
Triple-Reassortant Swine Virus Seen Since 2005 in US. Last Updated: May 07, 2009. ... triple-reassortant swine influenza A (H1) viruses -- have been documented since 2005 in the United States, according to a study ... The NEJM noted that the swine origin influenza virus (S-OIV) that causes the H1N1 flu is simply the latest strain of H1 ... The S-OIV will continue to mutate in unknown ways over the coming months and might even replace H1 virus as the seasonal flu ...
... is an important condition of influenza virus efficient replication, but a role of HA and NA specificities at oligosaccharide ... Reassortment between viruses leading to appearance of avian virus HA and human virus NA on the virion surface often resulted in ... Influenza A virus reassortants with surface glycoprotein genes of the avian parent viruses: effects of HA and NA gene ... Postreassortment changes in HA receptor-binding and NA substrate specificities for three reassortant/passage variant virus ...
We identified a reassortant H5 HA/H1N1 virus-comprising H5 HA (from an H5N1 virus) with four mutations and the remaining seven ... A human seasonal H1N1 virus, a wild-type avian H5 HA virus, and a mutant H5 HA virus were compared for their ability to bind to ... receptor-binding variants of H5N1 viruses with pandemic potential, including avian-human reassortant viruses as tested here, ... Experimental adaptation of an influenza H5 HA confers respiratory droplet transmission to a reassortant H5 HA/H1N1 virus in ...
... including Bluetongue virus (BTV). Recently, co-circulation of natural and vaccine BTV variants in Europe, and their ensuing ... may facilitate the appearance of clinically relevant reassortants via co-circulation of BTV strains of African, Asian and ... Reassortment contributes to the evolution of RNA viruses with segmented genomes, ... Viruses, EISSN 1999-4915, Published by MDPI Disclaimer The statements, opinions and data contained in the journal Viruses are ...
Although some H9-pandemic reassortant viruses (pathogenicity group I viruses) possessed higher virulence than parental viruses ... The single reassortant with BJ09 NA (r6 virus in Table 2) exhibited similar pathogenicity to those of the HB08 virus, whereas ... For reassortant viruses, 105 pfu virus was the highest dose used for inoculation. Three mice from each group were euthanized on ... ii) Reassortants with pathogenicity similar to that of the BJ09 virus (pathogenicity group II). A total of 11 reassortants (~15 ...
... found a hybrid influenza virus in swine that combines elements of the pandemic 2009 H1N1 virus and a Eurasian swine flu virus, ... suggesting that continued circulation of the pandemic virus in pigs could lead to novel viruses with the ability to infect ... The detection of the pandemic virus in pigs prompted a flu ... Swine reassortant suggests 2009 H1N1 virus could cause more ... NEWS SCAN: 2009 H1N1 virus reassortant, H7N7 as potential pandemic virus, rising legionellosis cases, cholera in Cameroon. ...
... resulted from reassortment between the highly virulent H5N8 strain from Korea with the N6 gene from a low-pathogenic H3N6 virus ... studies in chickens and ducks identified our isolate from December 2017 as a novel highly pathogenic avian influenza virus. It ... viruses from migratory birds in Chungnam and Gyeonggi Provinces, South Korea following a reported die-off of poultry in nearby ... Pathogenicity and genetic characterisation of a novel reassortant, highly pathogenic avian influenza (HPAI) H5N6 virus isolated ...
Identification of HPAIVs in wild birds is significant as there is a potential risk of transmission of these viruses to poultry ... With the exception of the polymerase acidic (PA) gene, the viruses were most closely related to A/duck/Guangdong/01.01 ... The lack of more recent viruses to A/environment/Korea/W133/2006 (H7N7) indicates the... ... SZSGXJK005-Y/2016 (H5N6) (98.90 ~ 99.74%). The PA genes of the two novel Gangjin H5N6 viruses were most closely related to AIV ...
... J Infect. 2019 Apr 30 submited by kickingbird at May, 8, ... The PB2 and M genes of genotype S H9N2 virus contribute to the enhanced fitness of H5Nx and H7N9 avian influenza viruses in ... A/GD/277/H3N2/2017 is a novel reassortant of EA-H1N1 and H3N2 previously circulating in swine in Southern China.. ?Phylogenetic ... Molecular epidemiology and genetic characterization of influenza B virus in Lebanon during 2016~2018 2 days ago ...
Effect of gene constellation and postreassortment amino acid change on the phenotypic features of H5 influenza virus ... reassortants. Download Prime PubMed App to iPhone, iPad, or Android ... H1N1 SubtypeInfluenza A Virus, H5N1 SubtypeInfluenza A Virus, H5N2 SubtypeMicePhenotypeReassortant VirusesRecombination, ... A reassortant having HA and NA genes from A/Duck/Primorie/2621/2001 virus and 6 genes from A/Puerto Rico/8/34 virus (6:2 ...
... the H1N1pdm09 viruses frequently reassorted with endemic swine influenza viruses, including H3N2 triple-reassortant viruses and ... Novel H3N2 influenza viruses (H3N2v) containing seven genome segments from swine lineage triple-reassortant H3N2 viruses and a ... Novel swine influenza viruses with various combinations of pandemic, triple-reassortant, and Eurasian influenza virus segments ... These triple-reassortant H3N2 viruses cocirculated with classical H1N1 viruses in swine and exchanged genome segments via ...
The H5N1 hybrid viruses revealed a broad range of viability and multiplication capacity in cell cultures. In addition, several ... The introduction of avian genes resulted in a sudden change of the virus surface antigens, allowing its worldwide spread due to ... The highly pathogenic avian influenza H5N1 virus has continued its spread in domestic and wild birds in Asia, Europe, and ... In this study, we used recombinant DNA technology to generate a systematic collection of hybrid viruses (with genes from human ...
A seasonal reassortant A(H1N2) influenza virus harbouring genome segments from seasonal influenza viruses A(H1N1)pdm09 (HA and ... Case of seasonal reassortant a(H1N2) influenza virus infection, the Netherlands, March 2018. Publication. Publication. ... Case of seasonal reassortant a(H1N2) influenza virus infection, the Netherlands, March 2018. Eurosurveillance, 23(15). doi: ...
Nasal viral shedding observed in in vivo experiment 2 with reassortant viruses. The virus titers in nasal swabs specimens from ... S8B in the supplemental material). The internal genes of five human-like H3 viruses (the first H3N2 virus and four H3N1 viruses ... The human-like H3N2 virus detected first appears to be a precursor to the H3N1 viruses, differing from the H3N1 virus primarily ... reverse genetics-generated reassortants between the swine human-like H3N1 virus and the seasonal human H3N2 virus were tested ...
1.2.2 Investigate virus-specific factors associated with zoonotic and pandemic potential that confer cross-species infectivity ...
Human infection with a novel reassortant Eurasian-avian lineage swine H1N1 virus in northern China. ... Influenza A virus infections occur in different species, causing mild to severe respiratory symptoms that lead to a heavy ... An influenza A(H1N1) virus was isolated from a boy who was suffering from fever and headache and designated as A/Tianjin-baodi/ ... Full-genome sequencing and phylogenetic analysis revealed that A/Tianjin-baodi/1606/2018(H1N1) is a novel reassortant EAS-H1N1 ...
This virus was found to be phylogenetically related to a triple reassortant influenza virus which emerged in Canadian swine in ... Characterization of a Canadian mink H3N2 influenza A virus isolate genetically related to triple reassortant swine influenza ... of a Canadian mink H3N2 influenza A virus isolate genetically related to triple reassortant swine influenza virus. Journal of ... The transmission of the virus from swine to mink seems to have occurred following the feeding of animals with a ration composed ...
... some of which may be reassortants of existing viruses, and some of which may be reassortants of extinct viruses. If this ... Viruses of the family Bunyaviridae: are all available isolates reassortants?. K-REx Repository. Search K-REx. This Collection. ... Viruses of the family Bunyaviridae: are all available isolates reassortants?. Briese, Thomas; Calisher, Charles H.; Higgs, ... Viruses of the family Bunyaviridae (the bunyaviruses) possess three distinct linear, single-stranded, negative sense or ...
"Isolation and genetic characterization of novel reassortant H6N6 subtype avian influenza viruses isolated from chickens in ... Two novel reassortants of avian influenza A (H5N6) virus in China. Bi, Y; Mei, K; Shi, W; Liu, D; Yu, X; Gao, Z; Zhao, L; Gao, ... These novel reassortant viruses showed moderate pathogenicity in mice and were able to replicate in mice without prior ... Reassortant highly pathogenic influenza A(H5N6) virus in Laos. Wong, FY; Phommachanh, P; Kalpravidh, W; Chanthavisouk, C; ...
The well-known Toscana virus (TOSV) was isolated; three new, closely related phleboviruses differing in their M segments and ... Such a complex situation emphasizes the need for detailed investigations of the biology of these viruses to better characterize ... The co-circulation, in a restricted area, of three viruses characterized by different M segments, likely resulted from ... while the Ponticelli viruses fall within the Salehabad phlebovirus species. Results highlight an unexpected diversity of ...
Production of reassortant viruses containing human rotavirus VP4 and SA11 VP7 for measuring neutralizing antibody following ... Production of reassortant viruses containing human rotavirus VP4 and SA11 VP7 for measuring neutralizing antibody following ... Production of reassortant viruses containing human rotavirus VP4 and SA11 VP7 for measuring neutralizing antibody following ... Production of reassortant viruses containing human rotavirus VP4 and SA11 VP7 for measuring neutralizing antibody following ...
... is a reassortant that acquired its small and large genome segments from Main Drain virus and its medium genome segment from an ... The novel genome organization of the insect picorna-like virus Drosophila C virus suggests this virus belongs to a previously ... Detection of Fowlpox virus carrying distinct genome segments of Reticuloendotheliosis virus. Virus Research 260: 53-59, 2019 ... Sequence analysis of genome segments S4 and S8 of Mal de Río Cuarto virus (MRCV): evidence that the virus should be a separate ...
"Emergence of novel reassortant H3N2 influenza viruses among ducks in China, Archives of Virology" on DeepDyve, the largest ... H1N1 swine viruses and H5N1 avian virus. The emergence of H3N2 virus with incorporation of an H5N1 virus gene raises new ... H1N1 swine viruses and H5N1 avian virus. The emergence of H3N2 virus with incorporation of an H5N1 virus gene raises new ... Emergence of novel reassortant H3N2 influenza viruses among ducks in China. Emergence of novel reassortant H3N2 influenza ...
Influenza A Virus, H9N2 Subtype Influenza In Birds Lakes Molecular Sequence Data Phylogeny Reassortant Reassortant Viruses ... Phylogenetic and antigenic characterization of reassortant H9N2 avian influenza viruses isolated from wild waterfowl in the ... Our analysis of viruses from domestic ducks at Tanguar haor, Bangladesh, showed genetic similarities with other viruses from ... Antigenic analyses indicated that these viruses were significantly different from the Eurasian lineage viruses. Conclusions ...
Emergence of a New Swine H3N2 and Pandemic (H1N1) 2009 Influenza A Virus Reassortant in Two Canadian Animal Populations, Mink ... A swine H3N2 (swH3N2) and pandemic (H1N1) 2009 (pH1N1) influenza A virus reassortant (swH3N2/ pH1N1) was detected in Canadian ... 2009 influenza A virus reassortant in two Canadian animal populations, mink and swine. Journal of Clinical Microbiology, 49(12 ... Simultaneously, a similar virus was also detected in Canadian mink based on partial viral genome sequencing. The origin of the ...
Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in ... Pathogenic Characterization and Full Length Genome Sequence of a Reassortant Infectious Bursal Disease Virus Newly Isolated in ...
  • The 1918 H1N1 virus likely derived all eight genes from an avian virus and accumulated mutations during adaptation in a mammalian host ( 7 , 8 ). (
  • The NEJM noted that the swine origin influenza virus (S-OIV) that causes the H1N1 flu is simply the latest strain of H1 hemagglutinin virus which first appeared in both humans and swine in 1918 and has returned in different variants ever since. (
  • H1N1 viruses reassorted in swine, and the resulting swine method ( 13 ). (
  • Experimental adaptation of an influenza H5 HA confers respiratory droplet transmission to a reassortant H5 HA/H1N1 virus in ferrets. (
  • We identified a reassortant H5 HA/H1N1 virus-comprising H5 HA (from an H5N1 virus) with four mutations and the remaining seven gene segments from a 2009 pandemic H1N1 virus-that was capable of droplet transmission in a ferret model. (
  • The coexistence of H9N2 and pandemic influenza H1N1/2009 viruses in pigs and humans provides an opportunity for these viruses to reassort. (
  • To evaluate the potential public risk of the reassortant viruses derived from these viruses, we used reverse genetics to generate 127 H9 reassortants derived from an avian H9N2 and a pandemic H1N1 virus, and evaluated their compatibility, replication ability, and virulence in mice. (
  • All reassortants with higher virulence than parental viruses contained the PA gene from the 2009 pandemic virus, revealing the important role of the PA gene from the H1N1/2009 virus in generating a reassortant virus with high public health risk. (
  • Our results indicate that some avian H9-pandemic reassortants could emerge with a potentially higher threat for humans and also highlight the importance of monitoring the H9-pandemic reassortant viruses that may arise, especially those that possess the PA gene of H1N1/2009 origin. (
  • Pandemic H1N1/2009 influenza virus has spread by human-to-human transmission across the globe at an unprecedented rate since it was first isolated from humans in Mexico in 2009 ( 14 , 15 , 16 ). (
  • Additionally, pandemic H1N1/2009 influenza viruses were also frequently isolated from pigs ( 17 - 19 ) that were proposed to be "mixing vessels" for the reassortment of influenza viruses. (
  • Coinfection with H9N2 and pandemic H1N1/2009 influenza viruses in the same host (e.g., pigs and humans) provides the opportunity for reassortment between these viruses. (
  • These facts remind us that avian H9N2 influenza viruses could acquire some functions critical for pandemic strains by reassortment with pandemic H1N1 influenza viruses when infecting the same host. (
  • Furthermore, previous studies revealed that frequent reassortment is an important evolution mechanism of H9N2 influenza viruses ( 4 , 5 ) and that the pandemic H1N1/2009 influenza virus had already reassorted with the H1N1 swine influenza virus ( 24 ). (
  • Among 36 isolates detected, one group had surface genes from a Eurasian avian-like H1N1 virus and internal genes from the 2009 H1N1 strain. (
  • Also, ferrets that were immunized against the 2009 H1N1 virus had only partial protection against the reassortant strain. (
  • The authors say the continuing prevalence 2009 H1N1 virus in pigs "could lead to the genesis of novel swine reassortant viruses with the potential to infect humans. (
  • A/GD/277/H3N2/2017 is a novel reassortant of EA-H1N1 and H3N2 previously circulating in swine in Southern China. (
  • Reassortants between a low-pathogenic avian influenza virus strain A/Duck/Primorie/2621/2001 (H5N2) and a high-yield human influenza virus strain A/Puerto Rico/8/34 (H1N1) were generated, genotyped and analyzed with respect to their yield in embryonated chicken eggs, pathogenicity for mice, and immunogenicity. (
  • Novel H3N2 influenza viruses (H3N2v) containing seven genome segments from swine lineage triple-reassortant H3N2 viruses and a 2009 pandemic H1N1 (H1N1pdm09) matrix protein segment (pM) were isolated from 12 humans in the United States between August and December 2011. (
  • Humans are periodically infected with zoonotic influenza viruses from swine, with at least 27 influenza viruses of swine origin of the A/H1N1, A/H1N2, and A/H3N2 subtypes having been identified in humans in the United States between 1990-2011 ( 32 ). (
  • However, as highlighted by the H1N1 pandemic of 2009 ( 11 , 33 ), swine influenza viruses that evolve the capacity for human-to-human transmission can lead to global pandemics, and therefore, the early stages of stuttering human transmission must be closely monitored. (
  • Currently, influenza A viruses of the H1N1, H1N2, and H3N2 subtypes cocirculate in U.S. swine. (
  • In 1998-1999, a triple-reassortant H3N2 influenza virus was identified in U.S. swine that possessed H3, N2, and PB1 segments of seasonal human H3N2 virus origin, PB2 and PA segments of avian virus origin, and NP, M, and NS segments of classical H1N1 swine virus origin ( 38 ). (
  • These triple-reassortant H3N2 viruses cocirculated with classical H1N1 viruses in swine and exchanged genome segments via reassortment, generating H1N2 viruses ( 17 ). (
  • A seasonal reassortant A(H1N2) influenza virus harbouring genome segments from seasonal influenza viruses A(H1N1)pdm09 (HA and NS) and A(H3N2) (PB2, PB1, PA, NP, NA and M) was identified in March 2018 in a 19-months-old patient with influenza-like illness (ILI) who presented to a general practitioner participating in the routine sentinel surveillance of ILI in the Netherlands. (
  • We characterized two novel swine human-like H3N2 and H3N1 viruses with hemagglutinin (HA) genes similar to those in human seasonal H3 strains and internal genes closely related to those of 2009 H1N1 pandemic viruses. (
  • Eurasian avian-like swine influenza A(H1N1) viruses (EAS-H1N1) are predominant in pigs and occasionally infect humans. (
  • An influenza A(H1N1) virus was isolated from a boy who was suffering from fever and headache and designated as A/Tianjin-baodi/1606/2018(H1N1). (
  • Full-genome sequencing and phylogenetic analysis revealed that A/Tianjin-baodi/1606/2018(H1N1) is a novel reassortant EAS-H1N1 containing gene segments from EAS-H1N1 (HA and NA), classical swine H1N1(NS) and A(H1N1)pdm09(PB2, PB2, PA, NP and M) viruses. (
  • The isolation and analysis of A/Tianjin-baodi/1606/2018(H1) provide further evidence that EAS-H1N1 poses a threat to human health and greater attention should be paid to surveillance of influenza virus infection in pigs and humans. (
  • for PB2, two of these isolates fell into the cluster of the H5N1 duck isolates, indicating a reassortment among H3N2, H1N1 swine viruses and H5N1 avian virus. (
  • A swine H3N2 (swH3N2) and pandemic (H1N1) 2009 (pH1N1) influenza A virus reassortant (swH3N2/ pH1N1) was detected in Canadian swine at the end of 2010. (
  • The emergence of new reassortant variants between human viruses such as A (H1N1)pdm09 and H5N1 HPAI virus, potentially generating reassortants with the transmissibility of the 2009 H1N1 virus and the virulence of the HPAI H5N1 viruses, would pose a threat to public health ( 7 ). (
  • The 2009 pandemic H1N1 virus (pH1N1) was derived through reassortment of North American triple reassortant and Eurasian avian-like swine influenza viruses (SIVs). (
  • To investigate viral reassortment, we coinfected cell cultures and a group of pigs with or without preexisting immunity with a Eurasian H1N1 virus, A/Swine/Spain/53207/2004 (SP04), and a North American triple reassortant H1N1 virus, A/Swine/Kansas/77778/2007 (KS07). (
  • Given the present extensive co-circulation in pigs of Eurasian avian-like (EA) swine H1N1 and 2009 pandemic (pdm/09) H1N1 viruses, reassortment between them is highly plausible but largely uncharacterized. (
  • Here, we investigated the consequences of a virus with the polymerase of pandemic H1N1 2009 acquiring an NS gene segment derived from a seasonal influenza A H3N2 virus, a combination that might arise during natural reassortment of viruses that currently circulate in humans. (
  • Here, in a mouse model, H1N1 A/Puerto Rico/8/34 (PR/8) reassortants that contained the H5N1/97 NS gene, the H5N1/01 NS gene, or an altered H5N1/97 NS gene encoding a Glu 92 →Asp substitution in NS1 was studied. (
  • M protein correlates with the receptor-binding specificity of haemagglutinin protein of reassortant influenza A (H1N1) virus. (
  • From the reassortment experiments between A/Aichi/4/92 and A/WSN/33 (WSN) (H1N1) viruses, two different phenotype viruses which contained the haemagglutinin (HA) gene from A/Aichi/4/92 virus and the neuraminidase (NA) gene from WSN virus were obtained. (
  • Next generation sequencing at CDC revealed a new seasonal human influenza A(H3N2) and A(H1N1)pdm09 reassortant virus, rather than an influenza A(H3N2) variant virus of swine origin. (
  • H5N1 virus with genes from H1N1 can spread through the air between mammals. (
  • In March-April 2009, a novel pandemic H1N1 emerged in the human population in North America (2) and demonstrated in a public forum the paucity of data on influenza viruses in swine. (
  • Other than sporadic transmission to humans (5,6), swine influenza A viruses of the H1N1 subtype historically have been distinct from avian and other mammalian H1N1 influenza viruses in characteristics of host specificity, serologic cross-reactivity, and/or nucleotide sequence. (
  • The emergence of the 2009 pandemic H1N1 (pH1N1) virus brought a heightened awareness to the evolution and epidemiology of influenza A viruses in swine and presents a new era of challenges and opportunities for understanding and controlling influenza in pigs. (
  • Since 2005, H1N1 and H1N2 viruses with the HA gene derived from human viruses emerged and spread across the US in swine herds (13). (
  • cluster viruses were shown to have most likely emerged from two separate introductions of human seasonal HA from H1N2 and H1N1 viruses and are differentiated phylogenetically by two distinct sub-clusters, ?1 and ?2, respectively (14). (
  • A reassortant influenza A subtype H1N2 virus with gene segments from seasonal A(H1N1)pdm09 virus (HA, MP, NP, NS, PA, PB1 and PB2) and seasonal A(H3N2) virus (NA) was identified in a routine surveillance sample in Denmark. (
  • October 21, 2011 - - CDC has confirmed the fifth case of human infection with a swine-origin influenza A (H3N2) virus that carries the M gene from the 2009 H1N1 virus. (
  • This case brings the total number of confirmed cases of human infection with swine-origin influenza A viruses in the United States to 26 since 2005, with 13 of these having been infected with swine-origin influenza A (H3N2) viruses and five of these being the H3N2 virus with the M gene from the 2009 H1N1 virus. (
  • The acquisition of the M gene likely occurred as a result of swine being co-infected with the swine influenza A (H3N2) virus and the human 2009 H1N1 virus. (
  • These viruses have six gene segments (PB2, PB1, PA, HA, NP, and NS) closely related to those of the 2009 H1N1 pandemic viruses. (
  • Therefore, understanding of these viruses' pathogenicity and transmissibility may help to identify determinants of virulence of the 2009 H1N1 pandemic viruses and to elucidate potential human health threats posed by the TRS viruses. (
  • One known exception is the A(H1N1)pdm09 influenza virus. (
  • The A(H1N1)pdm09 influenza virus contained genes from pig, bird and human influenza viruses, in a combination that was never reported before 2009 in any part of the world. (
  • Hence, the A(H1N1)pdm09 influenza virus is, so far, the only SIV that has shown the capacity to spread rapidly between humans. (
  • The virus reported in our study (A/Hunan/42443/2015(H1N1), HuN) is highlighted in red, and the EA viruses isolated from mainland China previously are in blue. (
  • A/swine/Guangxi/BB1/2013 (BB1, H1N1)), which shared the highest similarities with HuN virus, is included for analysis in each tree. (
  • A solid circle, square, and triangle are shown at the beginning of the HuN, BB1, and 2 human EA H1N1 viruses, respectively. (
  • 2 Influenza A viruses are named by their HA and NA type, (eg, H1N1), and are often given 'strain' names that include their genus or type, host species if other than human, location of isolation, arbitrary laboratory number, and year of isolation (eg, A/Swine/Iowa/15/1930). (
  • In early 1999, classical H1N1 SIV reassorted with H3N2 SIV virus to create another reassortant virus, H1N2. (
  • 1,8 Further reassortment occurred in late 2002, wherein both the HA and NA genes of H3N2 SIV have been replaced by the classical H1 and N1 genes, thereby creating a reassortant, novel H1N1 SIV with avian internal genes (PA and PB2). (
  • To perform a systematic comparison of several highly pathogenic influenza viruses, we inoculated cynomolgus macaques (8 animals per group) with either influenza A/Vietnam/1203/2004 (referred to as H5N1), 1918HA/NA:A/Texas/36/91 (1918HANA), 1918HA/NA/NS:A/Texas/36/91 (1918HANANS), or the parental H1N1 A/Texas/36/91 (Texas) virus. (
  • In March and early April 2009, a new swine-origin influenza A (H1N1) virus (S-OIV) emerged in Mexico and the United States 1 . (
  • Classical swine H1N1 viruses have circulated in pigs in North America and other regions for at least 80 years 3 . (
  • This lineage became established and gradually replaced classical swine H1N1 viruses, and also reassorted in pigs with human H3N2 viruses (A/Port Chalmers/1/1973-like) 11 . (
  • Play media According to the United States Centers for Disease Control and Prevention (CDC), in humans the symptoms of the 2009 "swine flu" H1N1 virus are similar to influenza and influenza-like illness in general. (
  • The 2009 H1N1 virus is not zoonotic swine flu, as it is not transmitted from pigs to humans, but from person to person through airborne droplets. (
  • Soon after the emergence of the H1N1 virus in April 2009, ARS scientists at the National Animal Disease Center in Ames, Iowa, began research using virus samples provided by the Centers for Disease Control and Prevention (CDC). (
  • Shortly after the reports of the new H1N1 virus in North America, H1N1 virus outbreaks were reported on turkey breeder farms in Virginia and California in the United States as well as in Chile, Canada, and France. (
  • ARS scientists at the Southeast Poultry Research Laboratory (SEPRL) quickly evaluated the pathogenesis of the new H1N1 virus in bird species to determine the potential risk to the poultry industry. (
  • The first step was to evaluate whether current U.S H1N1 swine influenza vaccines can protect pigs from infection with the 2009 H1N1 influenza virus circulating in people. (
  • This research study also evaluated whether pre-existing titers in pigs previously infected with endemic H1N1 swine influenza viruses circulating in the U.S could protect against the 2009 H1N1 influenza virus. (
  • Second was to address whether meat, blood and tissue from pigs infected with the new 2009 H1N1 Influenza A Virus would be free of infectious virus. (
  • Between the 1930s and the 1990s, the most commonly circulating swine influenza virus among pigs-classical swine influenza A, known as H1N1-underwent little change. (
  • The 2009 H1N1 influenza virus is also a triple reassortent, but its lineage is different than the H1N1 influenza viruses currently circulating in U.S. pigs. (
  • Since the emergence of the 2009 pandemic H1N1 influenza A virus, surveillance has been enhanced across the country in humans through the FluWatch program and in swine through various provincial programs. (
  • As New Scientist pointed out last week , H1N1 clearly belongs to a class of viruses called "triple reassortants", which have circulated widely as the predominant flu viruses in North American pigs since 1998. (
  • While triple reassortants are common in North American swine, the novel H1N1 may well have first appeared in pigs wherever the virus has travelled - Mexico seems an obvious possibility, as the first known human cases emerged in there. (
  • on 28 April, a farm in Alberta, Canada, was quarantined after a worker who had recently returned from Mexico passed the new H1N1 virus to the pigs he was handling . (
  • The CDC notified WHO on April 17 that an unknown H1N1 influenza virus had been isolated from a person in California. (
  • To assess background pre-pandemic cross-reacting antibodies to the pandemic (H1N1) 2009 virus in older populations in Australia. (
  • The pandemic (H1N1) 2009 virus is a novel A(H1N1) quadruple-reassortant virus that contains genes from North American and Eurasian lineages of swine, avian, and human influenza A viruses. (
  • 1 - 4 The pandemic (H1N1) 2009 virus is genetically and antigenically different to the seasonal human influenza A(H1N1) viruses circulating over recent decades. (
  • What also wasn't tested was reassortment with other human influenza viruses, such as an H1N1 serotype. (
  • The H1N1 2009 virus is pandemic in many countries. (
  • Oseltamivir and Zanamivir have good number of interactions with H1N1 2009 virus and the scoring function also support to this result. (
  • The number of interaction and scoring function shows that Oseltamivir and Zanamivir will be able to effectively control the present pandemic H1N1 virus 2009. (
  • Kirti K, Pooja S and Rup L (2009) Swine flu virus H1N1: a threat to human health. (
  • Kou Z, Hu S and Li T (2009) Genome evolution of novel influenza a (H1N1) viruses in humans. (
  • 2008) Emergence of resistance to Oseltamivir among influenza A (H1N1) virus in Europe. (
  • Pigs vaccinated with CNPs-KAg exhibited an enhanced IgG serum antibody and mucosal secretory IgA antibody responses in nasal swabs, bronchoalveolar lavage (BAL) fluids, and lung lysates that were reactive against homologous (H1N2), heterologous (H1N1), and heterosubtypic (H3N2) influenza A virus strains. (
  • circulating A(H1N1) viruses and the neuraminidase protein is similar to that of the current A(H3N2) viruses, the seasonal flu vaccine should provide good protection against influenza virus as well as protection against the currently circulating seasonal A(H1N1), A(H3N2), and B viruses. (
  • Construct novel influenza A (H1N1) virus chimeric genes for development of broadly protective vaccine candidates, NIH/NIAID (USDHHS). (
  • Construction and immunogenicity evaluation of recombinant influenza A viruses containing chimeric hemagglutinin genes derived from genetically divergent influenza A H1N1 subtype viruses. (
  • Several papers reporting phylogenetic analyses of the gene sequences of the new pandemic swine-origin H1N1 virus (S-OIV) have been published. (
  • The NA gene of S-OIV is closest to that of European 'avian-like' H1N1 influenza viruses sampled in 1991/1993, its MP gene closest to that of H3N2 Asian 'avian-like' viruses sampled in 1999, and its other six genes are closest to those of North American H1N2 'triple-reassortant' viruses sampled in 1999/2000. (
  • The emergence of these viruses was remarkable because influenza among American pigs had historically been due almost exclusively to infection with classical H1N1 swine influenza viruses ( 3 , 5 , 11 ). (
  • Phylogenetic analyses demonstrated that Sw/IN/99 had resulted from reassortment between a classical H1N1 swine influenza virus, which supplied its HA gene segment, and one of the triple-reassortant swine H3N2 viruses, which supplied all of the remaining RNA segments ( 7 ). (
  • The viruses from Japan and France were shown to be products of reassortment between classical (Japan) or avian-like (France) swine H1N1 viruses and human-lineage H3N2 viruses ( 4 , 6 , 9 , 10 , 12 , 13 , 16 ). (
  • Reassortment between human H1N1 and H3N2 viruses is hypothesized to have initially created an H1N2 subtype virus, which subsequently acquired all six of its internal viral protein genes through reassortment with a wholly avian virus ( 2 ). (
  • In this report, we present evidence that H1N2 viruses of the same genotype as that of the initially isolated Sw/IN/99 virus have been isolated from pigs in at least six states in the United States, suggesting that H1N2 viruses are now cocirculating, along with both classical H1N1 and triple-reassortant H3N2 viruses, in the American swine population. (
  • Here, we report on a comparative ferret model that parallels the efficient transmission of H3N2 human viruses and the poor transmission of H5N1 avian viruses in humans. (
  • In this model, an H3N2 reassortant virus with avian virus internal protein genes exhibited efficient replication but inefficient transmission, whereas H5N1 reassortant viruses with four or six human virus internal protein genes exhibited reduced replication and no transmission. (
  • These findings indicate that the human virus H3N2 surface protein genes alone did not confer efficient transmissibility and that acquisition of human virus internal protein genes alone was insufficient for this 1997 H5N1 virus to develop pandemic capabilities, even after serial passages in a mammalian host. (
  • In contrast, the H2N2 and H3N2 viruses that caused pandemics in 1957 and 1968, respectively, were the result of reassortment between avian and human influenza A viruses, acquiring the neuraminidase (NA) and/or hemagglutinin (HA), and PB1 gene from an avian virus and other genes from the previously circulating human strain ( 9 ). (
  • Selection of the high-yield variants of the human-avian reassortants led either to twofold decrease in the affinity of HA for most α2-3-sialosides and the appearance of affinity for α2-6-sialosides (H3N2 reassortant), or to decreasing the HA affinity for SiaLe c and SiaLe a (H3N1 reassortant), or to enhancing the ability of NA to discriminate between α2-3/2-6 substrates (H4N1 reassortant). (
  • Characterization of sialidase from an influenza A (H3N2) virus strain: kinetic parameters and substrate specificity. (
  • Hemagglutination-inhibition test shows A/GD/277/H3N2/2017 is antigenically distinct from seasonal H3N2 viruses currently circulating in the human population. (
  • Phylogenetic analysis shows A/GD/277/H3N2/2017-like virus caused another spill-over infection in Vietnam in 2010 suggesting the firm establishment of this swine lineage in Southeast Asia. (
  • To understand the evolution of these novel H3N2 viruses in swine and humans, we undertook a phylogenetic analysis of 674 M sequences and 388 HA and NA sequences from influenza viruses isolated from North American swine during 2009-2011, as well as HA, NA, and M sequences from eight H3N2v viruses isolated from humans. (
  • Notably, these rH3N2p viruses were generated in swine via reassortment events between H3N2 viruses and the pM segment approximately 4 to 10 times since 2009. (
  • Importantly, the N2 segment of all H3N2v viruses isolated from humans is derived from a genetically distinct N2 lineage that has circulated in swine since being acquired by reassortment with seasonal human H3N2 viruses in 2001-2002, rather than from the N2 that is associated with the 1998 H3N2 swine lineage. (
  • Of particular concern is the observation that between 17 August and 23 December 2011, 12 humans in the United States were infected with a novel reassortant swine A/H3N2 influenza virus, termed H3N2v, that contains a matrix (M) protein derived from H1N1pdm09 viruses (pM) ( 3 , 4 , 5 ). (
  • In the last 10 years the majority of H1 and H3 viruses isolated from swine contain the triple-reassortant internal gene (TRIG) constellation (avian origin PB2 and PA, human H3N2 origin PB1, and classical swine origin NP, M, and NS), although whole-genome sequence data for swine influenza viruses in the U.S. are limited ( 28 ). (
  • Both viruses were antigenically distant from swine H3 viruses that circulate in the United States and from swine vaccine strains and also showed antigenic drift from human seasonal H3N2 viruses. (
  • Their pathogenicity and transmission in pigs were compared to those of a human H3N2 virus with a common HA ancestry. (
  • Both swine human-like H3 viruses efficiently infected pigs and were transmitted to indirect contacts, whereas the human H3N2 virus did so much less efficiently. (
  • To evaluate the role of genes from the swine isolates in their pathogenesis, reverse genetics-generated reassortants between the swine human-like H3N1 virus and the seasonal human H3N2 virus were tested in pigs. (
  • In 2007, an H3N2 influenza A virus was isolated from Canadian mink. (
  • Jin, Meilin 2011-06-01 00:00:00 During 2006-2009 influenza virus surveillance, three H3N2 viruses were isolated from ducks in Central China. (
  • The emergence of H3N2 virus with incorporation of an H5N1 virus gene raises new concerns about the generation of novel viruses that could affect humans. (
  • While pandemic preparedness attention is divided among the A (H5N1), A (H2N2), A (H9N2), A (H7Nx), and A (H3N2)v subtypes in various continents, the endemicity of H5N1 viruses in poultry in parts of Asia and Africa ( 5 , 6 ) poses a challenging threat to public health. (
  • In Madin-Darby canine kidney (MDCK) cells, the virus with the NS gene from the H3N2 parent showed enhanced replication, probably a result of increased control of the interferon response. (
  • Levels of viral RNA during single-cycles of replication were lower for the virus with H3N2 NS, and this virus reached lower titres in the lungs of infected mice. (
  • As part of routine surveillance, a second specimen collected during the emergency department visit on February 17 was forwarded to the Idaho Bureau of Laboratories (IBL), where CDC's influenza reverse transcription-polymerase chain reaction (RT-PCR) diagnostic panel detected both pandemic influenza A and H3, which suggested an influenza A(H3N2) variant virus of swine origin. (
  • After their emergence, the H3N2 viruses reassorted with cH1N1 swine IAV (11,12). (
  • Reassortant H1 viruses are endemic with the H3N2 viruses in most major swine producing regions of the U.S. and Canada. (
  • The triple reassortant H3N2 viruses were isolated for the first time from pigs in 1998 and are known to be endemic in swine and turkey populations in the United States. (
  • In 2004, we isolated two H3N2 triple reassortant viruses from two turkey breeder flocks in Ohio and Illinois. (
  • In this study, we evaluated three triple reassortant H3N2 isolates of turkey origin and one isolate of swine origin for their transmission between swine and turkeys. (
  • Later in the same year, we isolated another H3N2 TR virus from turkey breeder hens in Illinois that were vaccinated twice with a swine H3N2 TR virus. (
  • In a previous study (manuscript submitted) we observed major antigenic differences between turkey and swine H3N2 TR viruses. (
  • Although the transmission of H3N2 TR viruses from pigs to turkeys was suggested in previous reports [ 19 , 20 ], no experimental work has been done to support this premise. (
  • Subsequently three additional cases of human infection with swine-origin influenza A (H3N2) viruses carrying the same genetic change were detected in Pennsylvania. (
  • On October 14, 2011, CDC received a report from the state of Maine that an influenza virus specimen had tested positive for a likely swine influenza A (H3N2). (
  • CDC laboratory testing confirmed a case of human infection with swine-origin influenza A (H3N2) virus. (
  • Swine influenza A (H3N2) viruses normally infect pigs, but on rare occasions, can also infect humans. (
  • Visual Interpretation ) While we know the M gene plays a role in influenza virus infection, assembly and replication, the significance of this change in these swine-origin influenza A (H3N2) viruses is unknown at this time. (
  • Then, in 1998, a reassortant H3N2 SIV was detected in US swine. (
  • 6 During 1998, reassortant H3N2 strains of SIV emerged in the swine population, that were either double reassortant, containing gene segments from human and avian strains of influenza (eg, A/Sw/NC/98) or triple reassortant, containing gene segments from human, avian, and swine influenza strains (eg, A/Sw/TX/98). (
  • Following recent increased reporting of human infections in the US with an influenza A(H3N2) variant virus of swine origin (A(H3N2)v), ECDC has updated its risk assessment. (
  • It concludes that the swine-origin influenza A(H3N2)v viruses do not currently pose a serious risk to human health in general and Europe in particular. (
  • ECDC published an update of its previous rapid risk assessment on Swine-origin triple reassortant influenza A(H3N2) viruses in North America. (
  • CDC has reported recent infections in children in North America with a swine-origin triple reassortant influenza A(H3N2) virus that includes a genetic component from the pandemic 2009 virus, and with probable human-to-human transmission with these viruses. (
  • Still, the focus of the current research was on reassortants between influenza viruses of serotypes H5N1 ("bird flu") and human H3N2. (
  • To do this, they first used a human H3N2 virus, and four different H5N1 viruses (isolated in 1997, 2003, and two isolated in 2005) to validate their ferret transmission model, by housing ferrets together in a cage separated by a perforated wall. (
  • Then, they used reverse genetics to create reassortant influenza viruses, containing some human H3N2 genes and some avian H5N1 genes, which were then again used to infect a new batch of ferrets. (
  • H3N2 influenza A viruses have caused widespread outbreaks of respiratory disease and, in some cases, abortion among pigs throughout the major swine-producing regions of the United States since 1998. (
  • The most common genotype of H3N2 virus isolated to date is a triple reassortant containing hemagglutinin (HA), neuraminidase (NA), and PB1 polymerase genes of human influenza virus origin, matrix (M), nonstructural (NS), and nucleoprotein (NP) genes of classical swine influenza virus origin, and PA and PB2 polymerase genes of avian influenza virus origin ( 8 , 15 , 17 ). (
  • Subsequent to the appearance of these H3N2 viruses, an H1N2 virus (A/Swine/Indiana/9K035/99 [Sw/IN/99]) was isolated from a pig in Indiana during a 6-week-long outbreak of influenza-like illness and abortions on the farm of origin in November 1999. (
  • Avian influenza A H5N1 viruses continue to spread globally among birds, resulting in occasional transmission of virus from infected poultry to humans. (
  • Probable human-to-human transmission has been documented rarely, but H5N1 viruses have not yet acquired the ability to transmit efficiently among humans, an essential property of a pandemic virus. (
  • These results highlight the complexity of the genetic basis of influenza virus transmissibility and suggest that H5N1 viruses may require further adaptation to acquire this essential pandemic trait. (
  • Highly pathogenic avian influenza (HPAI) H5N1 viruses are now enzootic in several countries and are presently undergoing unprecedented geographic expansion among wild and domestic birds. (
  • 200 laboratory-confirmed human infections have been reported, primarily as a result of transmission of the H5N1 virus from domestic poultry to humans ( 1 - 4 ). (
  • Despite limited instances of probable human-to-human transmission ( 5 , 6 ), H5N1 viruses have not yet acquired the ability to transmit efficiently among humans. (
  • The continuing occurrence of human H5N1 infections underscores the ongoing public health threat and the urgent need to better understand the potential of H5N1 viruses to acquire properties that would confer efficient transmissibility among humans. (
  • H5N1 viruses isolated from humans to date possess all eight gene segments that are entirely avian in origin, and with only a few exceptions, have retained a receptor-binding site sequence in the HA that is typical of the avian virus preference for binding SA α2,3 ( 11 - 13 ). (
  • Therefore, despite considerable genetic diversity in H5N1 viruses isolated from humans since 1997, no consistent adaptation to the human host has been identified ( 14 ). (
  • Highly pathogenic avian H5N1 influenza A viruses occasionally infect humans, but currently do not transmit efficiently among humans. (
  • however, we do not know whether the four mutations in the H5 HA identified here would render a wholly avian H5N1 virus transmissible. (
  • Nevertheless, as H5N1 viruses continue to evolve and infect humans, receptor-binding variants of H5N1 viruses with pandemic potential, including avian-human reassortant viruses as tested here, may emerge. (
  • Our findings emphasize the need to prepare for potential pandemics caused by influenza viruses possessing H5 HA, and will help individuals conducting surveillance in regions with circulating H5N1 viruses to recognize key residues that predict the pandemic potential of isolates, which will inform the development, production and distribution of effective countermeasures. (
  • Thus, H9N2 influenza virus, along with H5N1 virus, is high on the list of candidates that could potentially cause another human influenza pandemic. (
  • Phylogenetic analysis revealed that Gangjin H5N6 viruses classified into Asian H5 clade lineage and were distinguishable from H5N8 and H5N1 HPAIVs previously isolated in Korea. (
  • Immunization of mice with an inactivated 6:2 H5N2 reassortant provided efficient immune protection against a reassortant virus containing the HA and NA genes of a recent H5N1 isolate. (
  • Using an established reverse genetics (rg) system for wild-type ( wt ) A/Leningrad/134/1957 and cold-adapted ( ca ) A/Leningrad/134/17/1957 (Len17) master donor virus (MDV), we produced and characterized three rg H5N1 reassortant viruses carrying modified HA and intact NA genes from either A/Vietnam/1203/2004 (H5N1, VN1203, clade 1) or A/Egypt/321/2007 (H5N1, EG321, clade 2) virus. (
  • A mouse model of infection was used to determine the infectivity and tissue tropism of the parental wt viruses compared to the ca master donor viruses as well as the H5N1 reassortants. (
  • Mice inoculated twice 4 weeks apart with the H5N1 reassortant LAIV candidate viruses developed serum hemagglutination inhibition HI and IgA antibody titers to the homologous and heterologous viruses consistent with protective immunity. (
  • These animals remained healthy after challenge inoculation with a lethal dose with homologous or heterologous wt H5N1 highly pathogenic avian influenza (HPAI) viruses. (
  • The profiles of viral replication in respiratory tissues and the immunogenicity and protective efficacy characteristics of the two ca H5N1 candidate LAIV viruses warrant further development into a vaccine for human use. (
  • The A (H5N1) highly pathogenic avian influenza (HPAI) virus reemerged in 2003 in Asia and subsequently spread to Africa, Europe, and the Middle East, becoming endemic in some countries. (
  • To date, human-to-human transmission of H5N1 HPAI viruses has been very limited, and most cases of infection in humans have occurred through close contact with infected live or dead poultry ( 1 , 2 ). (
  • The severity of disease caused in humans by H5N1 influenza viruses remains unexplained. (
  • The NS gene of Hong Kong H5N1/97 viruses was shown to contribute to high pathogenicity of reassortants in a pig model. (
  • In mice infected with reassortant virus containing the H5N1/97 NS gene, the mouse lethal dose (50 %) and lung virus titres were similar to those of PR/8, which is highly pathogenic to mice. (
  • Reassortants containing the altered H5N1/97 NS gene or the H5N1/01 NS gene demonstrated attenuated pathogenicity and lower lung titres in mice. (
  • Specific B- and T-cell responses were consistent with viral pathogenicity and did not explain the delayed clearance of the H5N1/97 NS reassortant. (
  • 8. A reassortant influenza A virus according to claim 1 characterized in that at least two gene segments are derived from an H5N1 strain. (
  • A nan Province, China, to a smallholder distributor in Luang sian lineage influenza A(H5N1) viruses continue to cause serious disease in poultry and sporadic hu- man infections ( 1 ). (
  • A(H5N1) virus and subsequently in poultry infected with clade 2.3.4 and 2.3.2 viruses in 2006 and 2008, respec- tively ( 2 , 3 ). (
  • Interclade reassortant influenza A(H5N1) vi- rus genotypes homologous to viruses circulating in south- ern China and Vietnam have also been detected, which indicated previous transboundary virus transfers. (
  • How- ever, influenza A(H5N1) virus in poultry has not been reported in Laos since mid-2010 ( 4 ). (
  • Evolutionary and transmission dynamics of reassortant H5N1 influenza virus in Indonesia. (
  • H5N1 highly pathogenic avian influenza (HPAI) viruses have seriously affected the Asian poultry industry since their recurrence in 2003. (
  • In this study, we present phylogenetic evidences for the interlineage reassortment among H5N1 HPAI viruses isolated from humans, cats, and birds in Indonesia, and identify the potential genetic parents of the reassorted genome segments. (
  • Scientists have created a form of the H5N1 avian flu virus that is transmissible between mammals, raising fears that it could trigger a human pandemic if it escapes from the lab - either through accidental release or as part of a bioterror attack. (
  • H9N2 viruses are distinct from the deadly Asian strain of H5N1 but are regarded as having the potential to evolve into a pandemic strain. (
  • In a first application of our method, we analyze data from an evolutionary experiment describing the growth of a reassortant H5N1 virus in ferrets. (
  • However there is no evidence of a significant change in the pattern of human illness and deaths related to A(H5N1) virus infections in the country. (
  • Mice vaccinated with VLPs were protected against challenge with lethal reassortant viruses expressing the H5N1 HA and NA, regardless if the H5N1 clade was homologous or heterologous to the vaccine. (
  • The results show that a non-replicating virus-like particle is effective at eliciting a broadened, cross-clade protective immune response to proteins from emerging H5N1 influenza isolates giving rise to a potential pandemic influenza vaccine candidate for humans that can be stockpiled for use in the event of an outbreak of H5N1 influenza. (
  • While much is known about circulation of zoonotic potential H5N1 and H9N2 AIVs in domestic poultry in Egypt, little is known about the pivotal role of migratory birds in the maintenance and transmission of the viruses in Egypt. (
  • However, a Qinghai-like H5N1 virus caused an outbreak in migratory waterfowl during 2005 before spreading from Asia to Europe and Africa ( 3 , 4 ). (
  • The outbreak gave rise to concerns that infections of wild birds with the highly pathogenic avian influenza (HPAI) virus subtype H5N1, which causes mild or no clinical signs in these birds, could result in transmission of the virus over long distances ( 5 , 6 ). (
  • As was the case in other wild birds, HPAI H5N1viruses were not known to be pathogenic in domestic ducks before 2002 ( 7 - 9 ), but since then, HPAI H5N1 viruses that are pathogenic in ducks have been isolated in many countries ( 3 , 5 , 10 , 11 ). (
  • Before 2010, H5N1 HPAI viruses among birds were detected mostly in poultry (chickens, domestic ducks, and quail), with the single exception of 1 magpie in 2004. (
  • The 'start' of the outbreak was given as 13 Apr 2014, 'pre-confirmation' on 18 Apr 2014, when the Laos Laboratory performed the real-time PCR test, preliminarily concluding that the virus was HPAI H5N1. (
  • To identify crucial components of the early host response during these infections by using both conventional and functional genomics tools, we studied 34 cynomolgus macaques ( Macaca fascicularis ) to compare a 2004 human H5N1 Vietnam isolate with 2 reassortant viruses possessing the 1918 hemagglutinin (HA) and neuraminidase (NA) surface proteins, known conveyors of virulence. (
  • Among these viruses, HPAI H5N1 was the most virulent. (
  • Within 24 h, the H5N1 virus produced severe bronchiolar and alveolar lesions. (
  • Notably, the H5N1 virus targeted type II pneumocytes throughout the 7-day infection, and induced the most dramatic and sustained expression of type I interferons and inflammatory and innate immune genes, as measured by genomic and protein assays. (
  • While both 1918 reassortant viruses also were highly pathogenic, the H5N1 virus was exceptional for the extent of tissue damage, cytokinemia, and interference with immune regulatory mechanisms, which may help explain the extreme virulence of HPAI viruses in humans. (
  • Since 2003, the mortality for highly pathogenic avian influenza (HPAI) of the H5N1 virus subtype has been 63% of reported cases ( ). (
  • The extreme virulence and rapidly fatal clinical outcomes of human H5N1 virus infections are reminiscent of the 1918 pandemic virus, which reportedly caused up to 100 million fatalities ( 5 ). (
  • Recent nonhuman primate experiments comparing HPAI H5N1 and a reconstructed 1918 virus suggest many similarities in early host responses to these viruses. (
  • The goal of the present study, conducted in our well-characterized macaque and systems biology model of influenza ( 12 - 15 ), was to refine our understanding by using a 2004 human H5N1 Vietnam isolate and 2 1918 reassortant viruses possessing the 1918 hemagglutinin (HA) and neuraminidase (NA) surface proteins, based on the role surface glycoproteins play in the high virulence of the 1918 virus in the mouse model ( 6 ). (
  • This study revealed important similarities but also critical differences between the H5N1 and 1918-reassortant viruses, highlighting aspects of the host-pathogen interface caused by highly virulent influenza viruses. (
  • Differential Replication, Lung Tissue Tropism, and Inflammatory and Innate Immune Responses in Macaques Infected with H5N1 and 1918 Reassortant Influenza Viruses. (
  • The increased reports of A(H5N1) outbreaks in poultry and wild bird populations, and the emergence of a further evolved lineage of the virus in poultry in some countries, do not change the current assessment of the risk to human health. (
  • Following reports of a human fatality due to highly pathogenic avian influenza A(H5N1) virus infection in China's Guangdong province, the European Commission requested an update to the assessment of risk of human-to-human transmission occurring. (
  • The results of two, as yet unpublished, investigations of laboratory-induced genetic changes in avian influenza A(H5N1) viruses have been reported to have found that a surprisingly few number of changes make the viruses transmissible between ferrets, the most commonly used model for the way influenza behaves in humans. (
  • But if most cases are relatively mild, like all so far reported, then even if this becomes a pandemic it isn't the kind of global catastrophe that would ensue if H5N1 became pandemic at any where near its current virulence (H5N1 has a case fatality ratio in excess of 60%, versus a case fatality ratio, so far, of 0% for this virus). (
  • After the reported spread of HPAI H5N1 virus in Asia, a large, interagency avian influenza virus, or AIV, surveillance effort was implemented throughout the United States during April 2006 to March of 2011. (
  • Highly pathogenic H5N1 influenza virus infection in migratory birds. (
  • As expected, the human virus spread from the infected to uninfected ferrets, but the H5N1 viruses did not. (
  • However, to generate these reassortants, they used the 1997 H5N1 virus--which, as they note, is "genetically distinct from H5N1 viruses isolated since 1997. (
  • I'm not sure why they chose this one--it seems that their findings would have been more relevant had they used a more recent H5N1 isolate, that was a better representative of the viruses circulating currently. (
  • Mihajlovic M and Mitrasinovic P (2009) Some novel insights into the binding of oseltamivir and zanamivir to H5N1 and N9 influenza virus neuraminidases: a homology modeling and flexible docking study. (
  • In this study, the HPAI (H5N2) virus was isolated from a commercial duck farm, giving evidence of the emergence of the first natural reassortment event in domestic poultry in Egypt. (
  • The virus was derived as a result of genetic reassortment between avian influenza viruses of H5N8 and H9N2 subtypes circulating in Egypt. (
  • Reassortment between viruses leading to appearance of avian virus HA and human virus NA on the virion surface often resulted in decreasing the replicative potential of the formed variants because of disturbance of a functional balance between "alien" HA and NA. (
  • Reassortment contributes to the evolution of RNA viruses with segmented genomes, including Bluetongue virus (BTV). (
  • For example, the pandemic influenza viruses of 1957 and 1968 emerged through genetic reassortment of avian viruses with the prevailing human viruses to possess novel antigenicity and efficient human-to-human transmissibility ( 22 , 23 ). (
  • It resulted from reassortment between the highly virulent H5N8 strain from Korea with the N6 gene from a low-pathogenic H3N6 virus from the Netherlands. (
  • Dual infections of arthropod and perhaps vertebrate and plant hosts provide substantial opportunity for segment reassortment and an increasingly recognized number of the nearly 300 viruses in this family have been shown to be reassortants. (
  • The co-circulation, in a restricted area, of three viruses characterized by different M segments, likely resulted from reassortment events. (
  • No reassortant containing a gene constellation similar to that of pH1N1 virus was found in either coinfected cells or pigs, indicating that the reassortment event that resulted in the generation of this virus is a rare event that likely involved specific viral strains and/or a favorable, not-yet-understood environment. (
  • The present study revealed high reassortment compatibility between EA and pdm/09 viruses in pigs, which could give rise to progeny reassortant viruses with enhanced virulence and transmissibility in mice and guinea pig models. (
  • Influenza viruses readily mutate by accumulating point mutations and also by reassortment in which they acquire whole gene segments from another virus in a co-infected host. (
  • Reassortment occurs when two influenza viruses infect a single host cell and exchange gene segments, creating a new virus. (
  • Influenza A reassortment is observed at high rates in animal and cell culture models, but a biologically successful human reassortant virus is rarely reported ( 1 - 3 ). (
  • The viruses pose a threat of emergence of a global pandemic influenza through point mutation or reassortment leading to a strain that can effectively transmit among humans. (
  • Widely used immunoprophylaxis can, however, provide high pressure which contributes to the genetic diversification of circulating viruses, e.g. through reassortment of genome segments. (
  • 2017 ). The simultaneous existence of the three AIV subtypes among different poultry populations in Egypt rates this country as a hotspot for the generation of new subtypes and genotypes of AIVs by reassortment (Naguib and Harder 2018 ), where a reassortant HPAIV H5N2 was recently reported in Egypt as a result of natural reassortment between the Egyptian LPAIV H9N2 and HPAIV H5N8 viruses (Hagag et al. (
  • Genetic analysis demonstrated that at least two genotypes of H5N6 were generated through reassortment between clade H5N8 HPAIVs and Eurasian low pathogenic avian influenza virus in migratory birds in late 2017, suggesting frequent reassortment of clade H5 HPAIVs and highlighting the need for systematic surveillance in Eurasian breeding grounds. (
  • classical reassortment, available since 1971 to generate hybrid viruses. (
  • Experts believe pigs can act as a 'mixing vessel' for the reassortment of avian, swine and human influenza viruses, and might play an important role in the emergence of novel influenza viruses that could be capable of causing a human pandemic similar to the virus in the current outbreak. (
  • In contrast, the H1N2 viruses in the United Kingdom resulted from multiple reassortment events. (
  • However, the relative contribution of human internal protein genes or other molecular changes to the efficient transmission of influenza viruses among humans remains poorly understood. (
  • matrix protein, nucleoprotein genes, nonstructural protein, The reassorted combinations have resulted in pandemic polymerase acid, polymerase basic 1, and polymerase basic viruses as well as low-pathogenicity viruses with low 2 were constructed by using the neighbor-joining method. (
  • Maximum-likelihood phylogenetic trees for A) hemagglutinin (HA) and B) neuraminidase (NA) genes of avian influenza viruses. (
  • Maximum-likelihood phylogenetic trees for polymerase basic 2 (PB2), PB1, acidic polymerase (PA), nucleoprotein (NP), matrix (M), and nonstructural protein (NS) genes of avian influenza viruses. (
  • A reassortant having HA and NA genes from A/Duck/Primorie/2621/2001 virus and 6 genes from A/Puerto Rico/8/34 virus (6:2 reassortant) replicated efficiently in embryonated chicken eggs, the yields being intermediate between the yields of the avian parent virus and those of the A/Puerto Rico/8/34 parent strain. (
  • The reassortant having the HA gene from A/Duck/Primorie/2621/2001 virus and 7 genes from A/Puerto Rico/8/34 virus (7:1 reassortant) produced low yields. (
  • A 5:3 reassortant generated by a back-cross of the 6:2 reassortant with the avian parent and having PB1, HA and NA genes of A/Duck/Primorie/2621/2001 virus produced higher yields than the 7:1 or 6:2 reassortants, although still lower than the yields of A/Puerto Rico/8/34 virus. (
  • The origin of the new swH3N2/pH1N1 viral genes was related to the North American swH3N2 triple-reassortant cluster IV (for hemagglutinin [HA] and neuraminidase [NA] genes) and to pH1N1 for all the other genes (M, NP, NS, PB1, PB2, and PA). (
  • H5 gene (98.94-99.24%), N6 gene (99.06-99.13%) However, the four isolated viruses differ from each other in some internal genes. (
  • Notably, nearly all these highly virulent reassortants (all except Gt13) were characterized with possession of EA H1 and full complement of pdm/09 ribonucleoprotein genes. (
  • We generated recombinant influenza viruses with surface HA and NA genes and matrix M gene segment from A/PR/8/34 virus, but different combinations of polymerase and NS genes. (
  • However, in mice the same virus was attenuated in comparison with the virus containing homologous pH1N1 polymerase and NS genes. (
  • Within the host cell the genetic material of a DNA virus is replicated and transcribed into messenger RNA by host cell enzymes, and proteins coded for by viral genes are synthesized by host cell ribosomes. (
  • Some viruses have only a few genes coding for capsid proteins. (
  • But no virus has the thousands of genes required by even the simplest cells. (
  • Moreover, our study also revealed significantly stronger diversifying selection on the M1 and PB2 genes in the lineages preceding and subsequent to the emergence of the reassortant viruses, respectively. (
  • Jan 7, 2009 (CIDRAP News) - Hong Kong health officials reported today that the H9N2 avian influenza virus that recently infected a 2-month-old girl from mainland China has not acquired any genes from human-adapted flu viruses, implying that it is unlikely to pose a major danger to humans. (
  • The gene constellation of the emerging virus was demonstrated to be a combination of genes from swine influenza A viruses (SIV) of North American and Eurasian lineages that had never before been identified in swine or other species. (
  • Although the eight-gene segments of the novel virus are similar to available sequences of corresponding genes from SIV from North America and Eurasia, no closely related ancestral IAV with this gene combination has been identified in North America or elsewhere in the world (3,4). (
  • However, their TRIG genes are similar to those found in the TRIG cassette of the contemporary swine triple reassortant viruses. (
  • Although all 4 viruses tested share high genetic similarity in all 8 genes, only the Ohio strain (A/turkey/Ohio/313053/04) was shown to transmit efficiently both ways between swine and turkeys. (
  • Phylogenetic analysis of al eight genes on A/Hunan/42443/2015 (HuN) viruses. (
  • 2,4,5 The highly conserved genes, nucleoprotein (NP) and matrix (M1), are used to classify influenza viruses as types A, B, and C. The hemagglutinin (HA) and neuraminidase (NA) genes encode for surface glycoproteins that project from the viral envelope. (
  • Phylogenetic analysis of influenza viruses collected during December 2009-February 2010 from chickens in live poultry retail shops in Lahore, Pakistan, showed influenza A(H9N2) lineage polymerase and nonstructural genes generate through inter- and intrasubtypic reassortments. (
  • AAVs are nonenveloped single-stranded DNA viruses used in gene therapy to insert copies of missing genes into host cells. (
  • It has been suggested that viruses belonging to the major genotypes Buan2 and Donglim3 might be reassortants containing the polymerase basic protein 2, hemagglutinin (HA), nucleoprotein, and neuraminidase (NA) genes from viruses in the outbreak in China during 2010 (A/duck/Jiangsu/k1203/2013 (H5N8) ( 17 ). (
  • Although the precise evolutionary pathway of the genesis of S-OIV is greatly hindered by the lack of surveillance data (see later), we can conclude that the polymerase genes, plus HA, NP and NS, emerged from a triple-reassortant virus circulating in North American swine. (
  • The genes of a flu virus are packaged in eight discrete segments. (
  • Triple reassortant means that these viruses carry a mixture of genes originally from pig, human and bird viruses. (
  • The other five genes are typical of other North American triple reassortants. (
  • Flu viruses have 8 different genes and in mixed infections sometimes shuffle those genes to form 'reassortants' with new combinations of the 8 genes chosen from those of the parents. (
  • Several reports have shown that six of the genes of S-OIV came from a 'triple-reassortant' influenza virus (or viruses). (
  • The other two genes (NA and MP) came from Eurasian 'avian-like' viruses common in Europe for longer, but never found in North America. (
  • Thus the NA and MP genes were most likely acquired by S-OIV from Eurasian 'avian-like' viruses on separate occasions, and therefore S-OIV probably had at least three parents. (
  • Phylogenetic analysis of the nucleo- fluenza virus strains H1N1pdm09 and H1N2, which were tide sequences was conducted by using MEGA version 5 prevalentinGunmaatthattime. (
  • We report on an isolated new reassortant H1N2 es are shown in the Figure, panels A and B. The identities of SIV derived from the pH1N1 virus and SIVs originating the nucleotide sequences of each gene are shown in the Ta- in Japan. (
  • This is the second reassortant influenza A(H1N2) virus identified in Europe in the 2018/19 influenza season, with the first case being detected December 2018 in Sweden. (
  • Influenza A virus subtype H1N2 (A/H1N2) is a subtype of the species Influenza A virus (sometimes called bird flu virus). (
  • Between December 1988 and March 1989, 19 influenza H1N2 virus isolates were identified in 6 cities in China, but the virus did not spread further. (
  • On February 6, 2002, the World Health Organization (WHO) in Geneva and the Public Health Laboratory Service (PHLS) in the United Kingdom reported the identification influenza A(H1N2) virus from humans in the UK, Israel, and Egypt. (
  • An H1N2 influenza A virus was isolated from a pig in the United States for the first time in 1999 (A. I. Karasin, G. A. Anderson, and C. W. Olsen, J. Clin. (
  • H1N2 viruses have been isolated subsequently from pigs in many states. (
  • Phylogenetic analyses of eight such viruses isolated from pigs in Indiana, Illinois, Minnesota, Ohio, Iowa, and North Carolina during 2000 to 2001 showed that these viruses are all of the same reassortant genotype as that of the initial H1N2 isolate from 1999. (
  • The Sw/IN/99 virus was the first H1N2 influenza virus isolated from a pig in the United States. (
  • However, H1N2 viruses were isolated previously from pigs in France in 1987 and 1988 ( 4 ), in Japan in 1978 to 1980 and 1989 to 1992 ( 6 , 9 , 10 , 12 , 13 , 16 ), and in the United Kingdom in 1994 and thereafter ( 1 , 2 ). (
  • The H1N2 viruses in France did not spread beyond their initial farms of origin ( 4 ), but the H1N2 viruses in Japan and the United Kingdom caused large-scale outbreaks of disease and spread widely in the swine populations of these countries ( 1 , 2 , 6 , 12 ). (
  • Most recently it has been shown that H1N2 viruses with HA proteins antigenically related to those of the H1N2 viruses from the United Kingdom are circulating among pigs in Belgium ( 14 ). (
  • The viral properties that confer transmissibility of influenza viruses among humans, and mammalian species in general, remains poorly understood, yet are clearly key factors that determine whether a novel subtype introduced into an immunologically naïve human population will result in a pandemic. (
  • Pandemic viruses of the 20th century arose in two ways. (
  • However, the earliest human H2 and H3 isolates differed from their avian counterparts in key receptor-binding residues that resulted in preferred binding of the human virus HA to sialic acid (SA) α2,6 receptors, suggesting that a shift from avian virus SA α2,3 to human virus SA α2,6 receptor-binding specificity is critical for efficient replication and spread of a pandemic strain ( 10 ). (
  • The detection of the pandemic virus in pigs prompted a flu virus surveillance program for pigs at slaughterhouses in southern China, according to the report by Chinese and American researchers. (
  • A genetic analysis of avian and human influenza viruses associated with the H7N7 avian flu outbreak in the Netherlands in 2003 suggests that flu viruses capable of causing a pandemic can emerge directly from poultry without passing through an intermediate host, says another report published yesterday by the Journal of Virology . (
  • This implies that HPAI viruses with pandemic potential can emerge directly from poultry," the authors write. (
  • The NS1 protein of the 1918 pandemic influenza virus blocks host interferon and lipid metabolism pathways. (
  • Scientists now know that the deadly bird flu virus is capable of causing a human pandemic. (
  • Following the emergence of the 2009 pandemic, this virus was also isolated from pigs in multiple areas of the world (including Europe), and it is currently circulating in pigs in several European countries. (
  • The mechanisms responsible for the virulence of the highly pathogenic avian influenza (HPAI) and of the 1918 pandemic influenza virus in humans remain poorly understood. (
  • During the first few weeks of surveillance, the virus spread worldwide to 30 countries (as of May 11) by human-to-human transmission, causing the World Health Organization to raise its pandemic alert to level 5 of 6. (
  • This virus has the potential to develop into the first influenza pandemic of the twenty-first century. (
  • Our results highlight the need for systematic surveillance of influenza in swine, and provide evidence that the mixing of new genetic elements in swine can result in the emergence of viruses with pandemic potential in humans 2 . (
  • These repeated outbreaks have increased concern that the H5N6 virus may cross over to humans and cause a pandemic. (
  • An increase in the number of its identified hosts, the expanding range of its distribution, and the continual evolution of H5N6 AIVs enhance the risk that an H5N6 virus may spread to other continents and cause a pandemic. (
  • Opinions were sought regarding the best means for the swine industry and all levels of government to work together to prevent and detect a potentially pandemic zoonotic influenza virus in Canada. (
  • Though the likelihood of a pandemic novel influenza virus arising at the swine-human interface is very low, pH1N1 demonstrated that it is possible for such a virus to emerge on the American continent. (
  • Prevention of a reassortant event that could lead to a pandemic novel influenza virus at the swine-human interface requires the prevention of direct and indirect contact between influenza infected persons and pigs. (
  • But researchers don't have a very good understanding of how new pandemic viruses emerge. (
  • Given ample opportunity to circulate, exchange genetic material with other viruses and improve its ability to infect and spread, one of these viruses could unexpectedly spark a pandemic. (
  • Pandemic influenza control measures need to focus more on younger adults naive to the pandemic virus and at increased risk of severe disease. (
  • 10 , 11 The significantly lower proportion of cases in older people may be explained by cross-reacting antibodies to the pandemic virus among this population. (
  • While the latter was long thought to be critical for the generation of a pandemic strain of virus (and was responsible for the 1957 and 1968 pandemics), we now know that the 1918 virus was not a reassortant, but instead, appears to have been a completely avian virus that adapted to a mammalian host via the accumulation of point mutations. (
  • Michaelis M, Doerr H and Cinatl JJ (2009) Novel swineorigin influenza a virus in humans another pandemic knocking at the door. (
  • Hayden F (2006) Antiviral resistance in influenza viruses-implications for management and pandemic response. (
  • In vivo studies of 73 of 127 reassortants revealed that all viruses were able to infect mice without prior adaptation and 8 reassortants exhibited higher pathogenicity than both parental viruses. (
  • Genetics, pathogenicity and transmissibility of novel reassortant H5N6 highly pathogenic avian influenza viruses first isolated from migratory birds in western China. (
  • The 7:1, 6:2 and 5:3 reassortants were pathogenic for mice, with the level of virulence close to A/Puerto Rico/8/34 virus, in contrast to the extremely low pathogenicity of the A/Duck/Primorie/2621/2001 parent strain. (
  • These novel reassortant viruses showed moderate pathogenicity in mice and were able to replicate in mice without prior adaptation. (
  • Exactly how these genetic changes might affect the behavior of the virus (if at all) isn't yet known, although Korea's CDC is conducting tests to determine its potential pathogenicity in humans. (
  • The pathogenicity of reassortant viruses, the induction of cytokines and chemokine CXCL1 (KC) in the lungs and specific B- and T-cell responses was characterized. (
  • Here we evaluated in a ferret model the pathogenicity and transmissibility of three groups of North American TRS viruses containing swine-like and/or human-like HA and NA gene segments. (
  • The study was designed only to detect informative and significant patterns in the transmissibility and pathogenicity of these three groups of viruses. (
  • A virus with reduced pathogenicity as a result of treatment or repeated passage through hosts. (
  • Chicken pathogenicity testing is compatible with low pathogenic avian influenza virus. (
  • In wild aquatic birds, low pathogenicity avian influenza viruses are in a state of evolutionary equilibrium, and infected hosts usually show no signs of disease. (
  • Although H5N8 subtype viruses have been detected previously in the United States, all have been low pathogenicity AIV of North American wild bird lineage. (
  • These glycoproteins also determine the host range, antigenicity and the pathogenicity of the viruses. (
  • The phylogenetic reassort and generate new viruses by cross-breeding in trees of hemagglutinin (HA) and neuraminidase (NA) the various hosts ( 1 ). (
  • Balanced action of hemagglutinin (HA) and neuraminidase (NA) is an important condition of influenza virus efficient replication, but a role of HA and NA specificities at oligosaccharide level in maintaining such a balance remains poorly studied. (
  • A variant of the 7:1 reassortant selected by serial passages in eggs had an amino acid substitution in the hemagglutinin (N244D, H3 numbering). (
  • The antigenic relatedness (R-value) between the turkey viruses and the swine virus (vaccine strain) was less than 30% as expressed by the Archetti and Horsfall formula [ 21 ] based on hemagglutinin inhibition (HI) and virus neutralization (VN) tests. (
  • Avian influenza virus (AIV), based on the antigenic properties of the hemagglutinin (HA) and neuraminidase (NA) proteins, has 16 HA subtypes and 9 NA subtypes (Krammer et al. (
  • Two major surface glycoproteins (proteins with a carbohydrate attached), called hemagglutinin (H) and neuraminidase (N), are how influenza A viruses are identified. (
  • The hemagglutinin and neuraminidase proteins are important targets for diagnostics and used to designate the subtype of the virus. (
  • Because the hemagglutinin protein of the virus is similar to that of the currently[when? (
  • Red indicates avian influenza A(H5N6) virus isolated in South Korea in this study, blue indicates human isolates, and green mammalian isolates. (
  • Specification of receptor-binding phenotypes of influenza virus isolates from different hosts using synthetic sialylglycopolymers: non-egg-adapted human H1 and H3 influenza A and influenza B viruses share a common high binding affinity for 6′-sialyl(N-acetyllactosamine). (
  • In addition, previous studies demonstrated that a significant proportion of H9N2 field isolates have acquired preference for a human virus-like receptor ( 10 , 13 ). (
  • Viruses of the family Bunyaviridae: are all available isolates reassortants? (
  • According to the phylogenetic analysis of complete genome sequences, the TOSV belongs to clade A, together with other Italian isolates, while the Ponticelli viruses fall within the Salehabad phlebovirus species. (
  • 1 This article will describe the structure of influenza viruses and provide information on how SIV isolates are defined by their antigenic and genetic characteristics. (
  • Follow-up sequencing of virus isolates from these samples confirms these findings. (
  • Furthermore, the unsampled history of the epidemic means that the nature and location of the genetically closest swine viruses reveal little about the immediate origin of the epidemic, despite the fact that we included a panel of closely related and previously unpublished swine influenza isolates. (
  • Representative specimens and virus isolates are sent to WHO Collaborating Centres (CCs) with more than 5,000 virus isolates characterized by CCs yearly. (
  • You can find a phylogenetic tree using the 1997 virus--HK486--compared to more recent isolates in this paper by many of the same authors). (
  • What would be an interesting experiment--but one that would probably be deemed a "fishing expedition"--would be to generate a panel of reassortants to inoculate into animals, and let selection take over--use the animals as the filter in order to identify unique isolates with a higher propensity for transmission from a mixed input inoculum. (
  • Genetic analysis and virulence studies in chickens and ducks identified our isolate from December 2017 as a novel highly pathogenic avian influenza virus. (
  • Compositionally, we demonstrated that EA H1-222G contributed to virulence by its ability to bind avian-type sialic acid receptors, and that pdm/09 RNP conferred the most robust polymerase activity to reassortants. (
  • The NS1 gene is a major virulence factor of influenza A virus. (
  • Influenza A virus NS1 gene mutations F103L and M106I increase replication and virulence. (
  • The in vivo study results are in contrast with the foregoing experimental investigations in which the natural reassortants exhibited an intermediate pathotype, and underline the complex nature of IBDV virulence. (
  • The most important part, though, is what the virulence of the virus is. (
  • Reassortant analysis of guinea pig virulence of Pichinde virus variants. (
  • Equine Amplification And Virulence Of Subtype IE Venezuelan Equine Encephalitis Viruses Isolated During The 1993 And 1996 Mexican Epizootics. (
  • The virulence of the virus. (
  • We report the genetic and phenotypic characterization of a field reassortant IBDV (designated as Bpop/03) that acquired segment A from very virulent IBDV and segment B from classical attenuated D78-like IBDV. (
  • The aim of this study was a genetic and pathotypic characterization of a reassortant IBD virus detected in Poland. (
  • Once developed, these candidate reassortants are sent to WHO CCs for characterization of their antigenic and genetic properties before being released to interested institutions on request. (
  • Author affiliations: Gunma Prefectural Institute of Public Health type viruses documented in Japan as the representative and Environmental Sciences, Maebashi-shi, Gunma, Japan strains, such as A/swine/Ehime/1/1980 (Figure, panel B). (
  • Similarly, the geographical features of the Mediterranean basin, which spans over portions of three continents, may facilitate the appearance of clinically relevant reassortants via co-circulation of BTV strains of African, Asian and European origins. (
  • On November 20, 2016 two novel strains of H5N6 highly pathogenic avian influenza virus (HPAIVs) were isolated from three whooper swans ( Cygnus cygnus ) at Gangjin Bay in South Jeolla province, South Korea. (
  • Such viruses are produced in cells coinfected with different strains of a given virus. (
  • RV5 contains 5 live reassortant rotavirus strains. (
  • The rotavirus parent strains of the reassortant viruses were isolated from human and bovine hosts. (
  • These recently appearing influenza A viruses have complicated disease management and control, in large part because endemic SIV continually infects susceptible pigs, 2 but also because several strains of SIV may be circulating in the herd concurrently. (
  • The attenuated strains are generated by passaging different virus pathotypes on cell culture or SPF chicken embryos resulting in loss of pathogenic capacity [ 1 ]. (
  • The goal of this project is to provide strategies for the generation of antigens and recombinant reassortant strains for future vaccine development based on rotavirus strains circulating in Africa. (
  • As rotavirus field strains are often difficult to isolate in cell culture, a novel reverse genetics system will be applied for rapid generation of specific replication-competent rotavirus reassortants containing antigenic determinants of African field strains. (
  • However, by the late 1990s, multiple strains and subtypes of triple reassortant swine influenza viruses-whose genomes include combinations of avian, human and swine influenza virus gene segments-had emerged and became predominant among North American pigs. (
  • With the current circulation of zoonotic HPAI and LPAI virus strains in Asia, increased understanding of the drivers responsible for the global spread of Asian poultry viruses via wild birds is needed. (
  • When Arabidopsis thaliana ecotype Col-0 was inoculated with a series of reassortant viruses created by exchanging viral genomic RNAs between two strains of cucumber mosaic virus (CMV), CMV(Y), and CMV(H), cell death developed in the leaves inoculated with reassortant CMV carrying CMV(H) RNA1 encoding 1a protein, but not in noninoculated upper leaves. (
  • Fluenz Tetra will help to protect against the four virus strains contained in the vaccine, and other strains closely related to them. (
  • We studied healthy infants approximately 6 to 12 weeks old who were randomly assigned to receive three oral doses of live pentavalent human-bovine (WC3 strain) reassortant rotavirus vaccine containing human serotypes G1, G2, G3, G4, and P[8] or placebo at 4-to-10-week intervals in a blinded fashion. (
  • In addition, Bayesian methods were used to elucidate the genetic diversity dynamics of the reassortant strain and one of its genetic parents, which revealed a more rapid initial growth of genetic diversity in the reassortant viruses relative to their genetic parent. (
  • Four reassortant rotaviruses express 1 of the outer-capsid proteins (G1, G2, G3, or G4) from the human rotavirus parent strain and the attachment protein (P7[5]) from the bovine rotavirus parent strain. (
  • In addition, a novel reassortant strain of the H6N2 subtype was identified which reveals the continuous risk of new influenza virus(es) introduction into Egypt. (
  • One is the ability of the viral strain to infect humans (there are many influenza viruses but most don't infect humans). (
  • Post-mortem examinations, including RT-PCR, and virus isolation, confirmed that the highly pathogenic H5N6 influenza virus was the causative agent, and the strain was named A/ Pavo Cristatus /Jiangxi/JA1/2016. (
  • Swine influenza virus (SIV) or swine-origin influenza virus (S-OIV) is any strain of the influenza family of viruses that is endemic in pigs. (
  • Novel influenza A viruses can occur through reassortant events occurring in cells simultaneously infected with more than one strain of influenza A virus. (
  • The H1 surface protein of the new virus is related to one that was in a strain of swine flu that circulated before the triple reassortants emerged, but it seems to have been evolving, somewhere, unnoticed for about a decade , according to this analysis from the University of Edinburgh , UK. (
  • If we had a better handle on the factors that caused an avian strain of influenza virus to be more efficiently transmitted among humans, then we could better focus our resources and know when to really sound the alarm--unlike now, when we're flying blind in many ways. (
  • H9N2 influenza viruses have been circulating worldwide in multiple avian species and repeatedly infecting mammals, including pigs and humans, posing a significant threat to public health. (
  • It is noteworthy that H9N2 influenza viruses in poultry have occasionally been transmitted to mammalian species, including humans and pigs ( 5 - 9 ). (
  • More than 50% of the pigs tested were found to be seropositive for one or more H1 flu viruses. (
  • Experiments showed that the virus could spread among pigs and from pigs to ferrets, and it could grow in human lung tissue in a laboratory. (
  • The experimental infections indicate that these novel H3 viruses are virulent and can sustain onward transmission in pigs, and the naturally occurring mutations in the HA were associated with antigenic divergence from H3 IAV from humans and swine. (
  • Data indicate that the swH3N2/pH1N1 virus can be found in several pigs that are housed at different locations. (
  • In pigs without or with preexisting immunity (immunized with commercial inactivated swine influenza vaccines) and coinfected with both viruses, six or seven reassortant viruses, as well as the parental viruses, were identified in bronchoalveolar lavage fluid samples from the lungs. (
  • Here, experimentally co-infected pigs with a representative EA virus and a pdm/09 virus yielded 55 novel reassortant viruses that could be categorized into 17 genotypes from Gt1 to Gt17 based on segment segregation. (
  • Most of reassortant viruses were more pathogenic and contagious than the parental EA viruses in mice and guinea pigs. (
  • The most transmissible reassortant genotypes demonstrated in guinea pigs (Gt2, Gt3, Gt7, Gt10 and Gt13) were also the most lethal in mice. (
  • Surveillance for influenza A viruses (IAV) circulating in pigs and other non-human mammals has been chronically under-funded and virtually non-existent in many areas of the world (1). (
  • The epidemiology of IAV in pigs dramatically changed after 1998 when triple reassortant viruses containing gene segments from the classical swine virus (NP, M, NS), human virus (PB1, HA, NA), and avian virus (PB2, PA) (8) became successfully established in the pig population (9). (
  • Pigs can become infected with and spread influenza viruses, including swine, human and avian influenza viruses. (
  • Human infection with swine-origin virus is mostly likely to occur when people are in close proximity to infected pigs. (
  • Ill pigs infected with flu viruses may exhibit signs similar to human influenza infections, such as coughing (barking), lack of appetite, runny nose and lethargy. (
  • Although this virus is likely of swine origin, it has not (to date) been detected in pigs prior to its appearance in humans. (
  • Transmission of the virus from pigs to humans is not common and does not always lead to human flu, often resulting only in the production of antibodies in the blood. (
  • Direct transmission of a swine flu virus from pigs to humans is occasionally possible (zoonotic swine flu). (
  • Classical swine influenza virus infections are enzootic among pigs in North America. (
  • Worldwide, more than 50 human cases of swine influenza virus infection, mostly due to classical swine influenza virus, have been documented in the past 35 years, with the greatest risk of infection among people with occupational exposure to live pigs. (
  • Swine influenza virus (SIV) is one of the primary causes of respiratory disease in growing pigs and can lead to major economic losses. (
  • Pigs have long been considered a potential source for new and novel influenza viruses that infect humans, as they have receptors on their cells that bind both mammalian and avian influenza viruses, increasing the opportunity for the exchange of genetic segments of the virus. (
  • Contemporary Epidemiology of North American Lineage Triple Reassortant Influenza A Viruses in Pigs. (
  • Does the new flu virus originate in pigs? (
  • Did this virus come from pigs, or not? (
  • There were reports from the US Department of Agriculture , and the World Organisation for Animal Health , that the virus had not been detected in pigs. (
  • Given international movements of both pigs and people, the virus could have emerged wherever the North American reassortants have travelled. (
  • If triple reassortants are bad news for both pigs and people, why haven't we got rid of them? (
  • it is antigenically similar to triple-reassortant swine influenza viruses found in pigs (and occasionally in humans) in the United States since the late 1990s. (
  • In CNPs-KAg vaccinated pigs challenged with heterologous virus reduced severity of macroscopic and microscopic influenza-associated pulmonary lesions were observed. (
  • In summary, chitosan SwIAV nanovaccine delivered by IN route elicited strong cross-reactive mucosal IgA and cellular immune responses in the respiratory tract that resulted in a reduced nasal viral shedding and lung virus titers in pigs. (
  • These viruses have been common in North American pigs for more than a decade, and have never been found in Europe. (
  • Both groups of viruses have however been found recently in pigs in SE Asia. (
  • We find that all are viruses of pigs. (
  • The PA gene belongs to classical Avian-like lineage and more likely originated from non-gull avian virus pool. (
  • The human lineage PB1, avian lineage PB2 and PA and swine lineage NP, M, and NS found in contemporary swine influenza viruses are referred to as the triple reassortant internal gene (TRIG) constellation (10) and the vast majority of the characterised swine viruses from the US and Canada contain the TRIG, regardless of subtype. (
  • The HAs from the human-like swine H1 viruses are genetically and antigenically distinct from classical swine lineage H1s. (
  • cluster were paired either with an N1 or N2 gene of human virus lineage and not of swine N1 lineage. (
  • In 2010, outbreaks of infection with the HPAI H5N8 virus derived from the Goose/Guangdong/1/1996 (Gs/GD) lineage were first reported in duck farms in Jiangsu, China ( 16 ). (
  • We sampled 1,129 wild birds on the Yukon-Kuskokwim Delta, Alaska, one of the largest breeding areas for waterfowl in North America, during spring and summer of 2015 to test for Eurasian lineage and intercontinental reassortant HP H5 IAVs and potential progeny viruses. (
  • Both viruses have 3 RNA segments of North American wild bird lineage and 5 RNA segments that showed more than 99 percent similarity to the 2014 Eurasian H5N8 viruses. (
  • First, the Eurasian lineage avian H5N8 virus survived introduction into North America in its entirety. (
  • In addition, phylogenetic trees based on the influenza viruses (SIVs) were transmitted to humans. (
  • A median-joining phylogenetic network of group C H5N6 viruses was constructed by using NETWORK version 5.0 with epsilon set to 0 (www.fluxus- (
  • Next-generation sequencing and phylogenetic analysis identified a reassortant Cache Valley virus. (
  • Sequence and phylogenetic data indicate that an orthobunyavirus recently detected in the Yucatan Peninsula of Mexico is a novel reassortant of Potosi and Cache Valley viruses. (
  • Phylogenetic analysis of the H5 viruses detected in the United States resulted in 3 major findings. (
  • Full-length genome sequencing of A/Mandarin_duck/Korea/K16-187-3/2016(H5N6) virus was performed by using conventional reverse transcription PCR and Sanger sequencing. (
  • A(H5N6) viruses. (
  • We investigated influenza A(H5N6) viruses from migratory birds in Chungnam and Gyeonggi Provinces, South Korea following a reported die-off of poultry in nearby provinces in November 2017. (
  • Genetic characterisation of novel, highly pathogenic avian influenza (HPAI) H5N6 viruses isolated in birds, South Korea, November 2016. (
  • Shen H , Wu B , Chen Y , Bi Y , Xie Q . Influenza A(H5N6) virus reassortant, southern China, 2014. (
  • Reassortant highly pathogenic influenza A(H5N6) virus in Laos. (
  • The lack of more recent viruses to A/environment/Korea/W133/2006 (H7N7) indicates the need for analysis of recent wild bird AIVs isolated in Korea because they might provide further clues as to the origin of these novel reassortant H5N6 viruses. (
  • What they found is that the Korean H5N6 virus has changed internally from its predecessors, and that - as we've seen previously - its genetic evolution continues. (
  • Like all influenza viruses, avian H5N6 is constantly changing. (
  • Six months ago, in EID Journal: Novel Reassortant H5N6 Viruses In Humans, Guangdong China, we looked at an analysis of 3 viruses collected last December in Guangdong Province, which found H5N6 had reassorted with both H9N2 and H6N6 since it emerged in 2014. (
  • The authors suggested there may be other - as yet undetected - H5N6 reassortants in the wild and others may yet emerge. (
  • In order to evaluate the harmfulness of the influenza H5N6 virus, the virus was provided to the Disease Control Headquarters of the Ministry of Health and Welfare on November 24, and the disease management headquarters will conduct an analysis on the human health risks. (
  • Clade viruses ( which include both H5N8 and H5N6 ) have demonstrated an enhanced ability to reassort with other - mostly LPAI - viruses, and continue to evolve and occasionally churn out viable novel subtypes. (
  • These birds were positive for In March 2014, avian influenza in poultry in Laos was avian influenza A virus (H5 subtype) by real-time reverse causedbyanemergentinfluenzaA(H5N6)virus.Genetic transcription PCR (RT-PCR) ( 5 ). (
  • We report highly pathogenic avian influenza (HPAI) in poultry in Laos in March 2014 that was caused by an emergent reassortant influenza A(H5N6) virus, apparently imported by live poultry from China. (
  • Sequencing analysis of original samples (post-mortem tissues) from both chickens and ducks shows that these are H5N6 highly pathogenic avian influenza viruses , with the highly pathogenic HA cleavage site sequence motif, PLRERRRKR*GLF . (
  • Novel H5N6 highly pathogenic avian influenza viruses (HPAIVs) were isolated from duck farms and migratory bird habitats in South Korea in November to December 2017. (
  • FG594-like H5N6 virus from Guangdong Province was the probable predecessor of JA1/2016, and the estimated divergence time was June 2014. (
  • Furthermore, we found that H5N6 influenza viruses can be classified into the two following groups: Group 1 and Group 2. (
  • Eurasian-origin and intercontinental reassortant highly pathogenic (HP) influenza A viruses (IAVs) were first detected in North America in wild, captive, and domestic birds during November-December 2014. (
  • The novel Eurasian highly pathogenic avian influenza HPAI A (H5N8) virus spread rapidly and globally during 2014, substantially affecting poultry populations. (
  • These appearances also represent a major change in Eurasian H5 virus circulation. (
  • The other external protein, N, plus the gene for one of the "internal" proteins of the virus is from Eurasian pig flu. (
  • The outbreak of highly pathogenic avian influenza H5Nx viruses in winter 2016/2017 was the most severe HPAI epizootic ever reported in Germany. (
  • Early in 2014, an outbreak of HPAI caused by a novel reassortant H5N8 virus occurred in Korea. (
  • however, they clustered with variant (reassortant) clade 2.3.4 H5 HPAI viruses from China of various NA subtypes. (
  • According to World Organisation for Animal Health guidelines, the virus was consistent with HPAI. (
  • LPAI and HPAI viruses co-circulate around the world, comprising a viral "gene pool. (
  • Highly pathogenic avian influenza (HPAI) viruses of subtype H5N8 were re-introduced into the Netherlands by late 2016, after detections in south-east Asia and Russia. (
  • Here we report on the detection of HPAI H5N8 virus in 57 wild birds of 12 species sampled during active (32/5,167) and passive (25/36) surveillance activities, i.e. in healthy and dead animals respectively, in the Netherlands between 8 November 2016 and 31 March 2017. (
  • These apparent differences between outbreaks and the continuing detections of HPAI viruses in Europe are a cause of concern. (
  • Influenza A viruses can be transmitted between humans, ( 11 ). (
  • Identification of HPAIVs in wild birds is significant as there is a potential risk of transmission of these viruses to poultry and humans. (
  • We identified 34 swine influenza viruses (termed rH3N2p) with the same combination of H3, N2, and pM segments as the H3N2v viruses isolated from humans. (
  • Approximately 1 month after the isolation of the H1N1pdm09 virus in humans ( 6 ), the virus was transmitted back to swine, with the first H1N1pdm09 virus being isolated from swine in Alberta, Canada, in May 2009 ( 16 ). (
  • Such a complex situation emphasizes the need for detailed investigations of the biology of these viruses to better characterize their pathogenic potential for mammals, including humans. (
  • These reassortants can now be applied to analyses of individual immune responses to VP4 and VP7 proteins after primary rotavirus infections and reinfections in humans. (
  • virus in humans and swine [ 2 ], but it is sporadic in birds. (
  • While there is not a vaccine to protect humans against these swine-origin influenza viruses, there are two FDA-cleared drugs that can be used to treat illness with these viruses. (
  • 2 As influenza A viruses cause disease in animals, birds, and humans, 3 including swine, this genus will be discussed in detail. (
  • Certainly there are no epidemiological data or analyses consistent with adaptation of these viruses to humans. (
  • The influenza virus is among the most devastating viral diseases due to the ease of spread as an aerosol and ability to cause severe sickness and mortality to susceptible humans. (
  • The virus is harmless to macaques or may cause only a herpetic rash in macaques, but in humans it often produces fatal infections of the brain and meninges. (
  • To determine the radiologic findings of human infection with a novel reassortant avian-origin influenza A H7N9 virus in March 2013, the first outbreak in humans. (
  • We show that it was derived from several viruses circulating in swine, and that the initial transmission to humans occurred several months before recognition of the outbreak. (
  • Second, some LPAI viruses have resulted in lethal infections in humans. (
  • Across Canada, among all respondents there was a concern regarding the transmission of influenza viruses among host species and recognition of the bidirectional transmission of viruses between humans and swine. (
  • One explanation of the different patterns of disease in Mexico and elsewhere, she said, might be that the virus has evolved to be less virulent as it passed through humans. (
  • 2009) Triple-Reassortant Swine Influenza A (H1) in Humans in the United States. (
  • WHO recommends that new reassortant candidate vaccine virus. (
  • Viruses in H3 subclade 3C.3a react poorly by focus reduction assay with ferret antisera raised against A/Singapore/INFMH-16-0019/2016(3C.2a1), signifying that the 2018-19 Northern Hemisphere influenza vaccine* might not be protective against this virus. (
  • Further provided are vaccine formulations comprising the reassortant influenza A virus of the invention. (
  • The H1 SIV are evolving by drift and shift while maintaining the TRIG backbone and the resulting viruses differ genetically and antigenically with obvious consequences for vaccine and diagnostic test development (14). (
  • At least eight amino acid changes were observed at the antigenic sites of the HA1 molecule between the turkey viruses and the swine vaccine virus. (
  • However it should be noted that seasonal influenza vaccine would NOT be expected to protect against this swine-origin influenza virus because it is so different from the human viruses in the seasonal vaccine. (
  • In February 2006, a live oral human-bovine reassortant rotavirus vaccine (RV5 [RotaTeq]) was licensed as a 3-dose series for use in infants in the United States. (
  • In February 2006, a live, oral human-bovine reassortant rotavirus vaccine (RV5) (RotaTeq [Merck and Co, Whitehouse Station, NJ]) was licensed for use in the United States. (
  • To address the need for improved influenza vaccines and alternatives to egg-based manufacturing, we have engineered an influenza virus-like particle (VLP) as a new generation of non-egg or non-mammalian cell culture-based candidate vaccine. (
  • In addition, novel systems for targeted generation of rotavirus reassortants and virus-like particles will be optimized, which may enable the rapid integration of newly emerging rotavirus variants into future vaccine formulations. (
  • High yield candidate vaccine viruses are developed by collaboration of laboratories involved in developing reassortants and WHO Collaborating Centres (CCs). (
  • Why influenza vaccine viruses need to be updated? (
  • Rapid spread of influenza viruses during seasonal epidemics and occasional pandemics tightly frames the whole process if vaccine is to be manufactured and delivered on time. (
  • A prerequisite of production and supply of an optimal influenza vaccine is the selection and development of optimal candidate vaccine viruses, and the development and availability of vaccine potency reagents. (
  • Vaccine virus selection has been conducted by the WHO Global Influenza Surveillance and Response System (GISRS) since 1973. (
  • We only chased this virus with vaccine rather than confront it," says Rodney Baker of Iowa State University, formerly a veterinarian for Premium Standard Farms , a major US pork producer. (
  • But before a swine vaccine can be put on the mass market, the US Department of Agriculture demanded extensive tests which take many months, if not years - by which time the flu virus evolved into something the vaccine no longer matched. (
  • By contrast, if you are only going to inject the vaccine back into the herd the virus came from, the rules are more relaxed. (
  • The failure to develop vaccines to protect against important infectious diseases such as human immunodeficiency virus type I (HIV-1) or Hepatitis C virus (HCV) has increased the interest in new vaccine strategies. (
  • The same approach was successfully used for another rhabdovirus, vesicular stomatitis virus (VSV), and opened the possibility to use rhabdoviruses as vaccine vehicles and biomedical tools. (
  • Functional human immunodeficiency virus type 1 (HIV-1) Gag-Pol or HIV-1 Gag-Pol and env expressed from a single rhabdovirus-based vaccine vector genome. (
  • Development of an HIV vaccine using a vesicular stomatitis virus vector expressing designer HIV-1 envelope glycoproteins to enhance humoral responses. (
  • A candidate swine influenza virus vaccine: in vivo evaluation of novel chimeric hemagglutinins expressed by parainfluenza virus 5 (PIV5) vector. (
  • Swine Flu Virus Created from Pig Vaccine? (
  • When a person is given the vaccine, the immune system (the body's natural defence system) will produce its own protection against the influenza virus. (
  • Fluenz Tetra vaccine viruses are grown in chicken eggs. (
  • But with the emergence of triple reassortants, losses began to mount and producers increasingly turned to vaccines in the hope of protecting their animals. (
  • Here we assess the molecular changes in HA that would allow a virus possessing subtype H5 HA to be transmissible among mammals. (
  • Wu, Nanping 2016-04-21 00:00:00 H6 subtype avian influenza viruses (AIVs) possess the ability to cross the species barrier to infect mammals and pose a threat to human health. (
  • Consignments from this batch were RT-PCR but negative for neuraminidase (NA) subtype N1 delivered to the villages a week later, and birds at both and were subjected to virus propagation in 9 to 11-day-old locations showed clinical signs of influenza and died sud- specific pathogen-free chicken eggs. (
  • These 4 samples were con- chicken sample from Luang Prabang and a duck sample firmed as positive for avian influenza virus (subtype H5) by from Xayabouly ( 6 ). (
  • These glycoproteins possess distinct antigenic properties and nucleotide gene sequences and thus are used to subtype influenza viruses into 16 HA types (types 1 to 16) and nine NA types (types 1 to 9). (
  • Thus, an influenza virus can be identified as to its subtype in an HI assay. (
  • A standard concentration of influenza virus (antigen) and serial dilutions of HA-subtype-specific antiserum are mixed, and after a short incubation period, RBCs are added to the antigen-antibody mixture. (
  • Beerens N , Heutink R , Bergervoet SA , Harders F , Bossers A , Koch G . Multiple Reassorted Viruses as Cause of Highly Pathogenic Avian Influenza A(H5N8) Virus Epidemic, the Netherlands, 2016. (
  • The H5N8 and H5N5 viruses detected in birds in Germany in 2016/2017 represent a reassortant swarm of at least five distinct genotypes, which carried closely related HA segments derived from clade (
  • An outbreak of highly pathogenic avian influenza, caused by a novel reassortant influenza A (H5N8) virus, occurred among poultry and wild birds in South Korea in 2014. (
  • Identification of H5N8 viruses in birds exposed to infected domestic ducks and mallards indicated that the viruses could spread by contact. (
  • Histologic and pathologic findings for the 3 raptors were consistent with those described in previous reports of H5N8 infections, and the severity of the lesions correspond to virus concentrations detected in the tissues by molecular assays. (
  • In contrast to the first H5N8 wave, local virus amplification with associated wild bird mortality has occurred in the Netherlands in 2016/17, with evidence for occasional gene exchange with low pathogenic avian influenza (LPAI) viruses. (
  • Highly pathogenic avian influenza A(H5N8) virus from waterfowl, South Korea, 2014. (
  • Novel reassortant influenza A(H5N8) viruses in domestic ducks, eastern China. (
  • In parallel, the low pathogenic avian influenza H9N2 virus has been endemic since 2010. (
  • H9N2 influenza viruses circulate worldwide and are endemic in multiple terrestrial avian species in Asia ( 1 - 4 ). (
  • In fact, several serological surveys revealed that a large number of people in China, ranging from 13.7% to 37.2%, might have evidence of prior infections of the H9N2 virus ( 11 , 12 ). (
  • The epidemiological and genetic findings so far suggest that the H9N2 virus has shown no signs of increased risk for human-to-human transmission," he said. (
  • The spokesman said the virus is very similar to an H9N2 virus isolated from a 9-month-old girl in Hong Kong in 2007. (
  • The H9N2 virus was not found in nasopharyngeal samples taken from the girl on Jan 2, the statement said. (
  • Dr. Daniel R. Perez at the University of Maryland and his colleagues have been studying avian H9N2 viruses in ferrets, which are considered the gold standard influenza animal model. (
  • The team previously showed when an avian H9N2 virus and a human virus exchanged genetic material, a resulting "reassortant" virus could replicate and transmit more effectively than the parent H9N2 virus. (
  • Antibodies that recognize this region in other H9N2 viruses, the researchers found, reacted poorly against the new reassortant virus. (
  • This study suggests that avian H9N2 viruses require little adaptation to gain the ability to spread through respiratory droplets. (
  • The exchange of the neuraminidase segment and high number of acquired mutations might be associated with an alteration in the biological propensities of this virus. (
  • Funning, T.G., Reid, A.H., Taubenberger, J.K.: Influenza A virus neuraminidase: regions of the protein potentially involved in virus-host interactions. (
  • However, neuraminidase treatment of COS cells expressing the HA protein of A/Aichi/4/92 virus or MDCK cells infected by PW10 virus restored the ability to adsorb CRBC. (
  • Influenza A viruses are classified according to their haemagglutinin (H) and neuraminidase (N) surface proteins. (
  • Sequencing of the viruses revealed that 3 amino acid changes on virus surface proteins-2 in the hemaglutinin protein (the "H" of the virus's name) and 1 in the neuraminidase protein (the "N")-were responsible for enabling respiratory droplet transmission. (
  • Viruses of the family Bunyaviridae (the bunyaviruses) possess three distinct linear, single-stranded, negative sense or ambisense RNA segments (large, medium, and small). (
  • All viruses in this genus have tripartite, single-stranded, negative-sense RNA genomes, and the three RNA segments are designated as small, (S), medium (M) and large (L). A 559 nt. (
  • This study provides evidence that LOKV is a natural reassortant that acquired its S and L RNA segments from MDV and its M RNA segment from an undiscovered, and possibly extinct, virus. (
  • Shift occurs when one virus swap out chunks of their genetic code with gene segments from another virus. (
  • Eight RNA gene segments comprise the influenza A virus genome. (
  • The influenza A virus gene segments, with the name of each gene, the protein encoded by it, and the function of the protein, are listed in Table 1. (
  • The virus possesses a bi-segmented genome (segments A and B) within a non-enveloped icosahedral capsid and is the causative agent of an immunosuppressive disease of young chickens [ 1 ]. (
  • n = 3), revealed three viral gene segments sharing high nucleotide identity with HP H5 viruses recently detected in North America. (
  • When two flu viruses infect the same host cell, the segments of each are copied and repackaged, 8 at a time, in new viral particles which then bud off from the infected cell. (
  • In this repackaging process the segments of the two different viruses may mix and match, so that new virus particle will have segments from two different viruses. (
  • It does have viral segments characteristic of two different families of swine flu, one typical of North America, where swine flu is endemic, and one typical of pig flu viruses from Europe and Asia. (
  • The genetic makeup of swine influenza viruses is identical to other influenza A viruses and consists of 8 segments of RNA that code for different proteins. (
  • Influenza viruses have the ability to exchange these segments, creating new genetically different viruses. (
  • The genome of this virus contains eight segments. (
  • The first influenza virus was isolated in 1930 by Shope (7) and was demonstrated to cause respiratory disease in swine that was similar to human influenza. (
  • Zaraket H, Saito R, Sato I and Suzuki Y (2009) Molecular evolution of human influenza a viruses in a local area during eight influenza epidemics from 2000 to 2007. (
  • These hybrid viruses showed high genetic compatibility and more than half replicated to a high titer in vitro. (
  • A virus consists of genetic material, which may be either DNA or RNA, and is surrounded by a protein coat and, in some viruses, by a membranous envelope. (
  • Because host cells do not have the ability to replicate "viral RNA" but are able to transcribe messenger RNA, RNA viruses must contain enzymes to produce genetic material for new virions. (
  • In other viruses a reverse transcriptase contained in the virion transcribes the genetic message on the viral RNA into DNA, which is then replicated by the host cell. (
  • Despite the mosaic genetic make-up, the virus caused high mortality (80%) in experimentally infected SPF chickens and induced lesions typical of the acute form of IBD. (
  • It is commonplace in nature that viruses with segmented genomes may exchange genetic material if they infect one cell at the same time. (
  • Prevalence and genetic characteristics of LP IAVs during the sampling period are concordant with previous findings of relatively low viral prevalence in geese during spring, non-detection of IAVs in geese during summer, and evidence for intercontinental exchange of viruses in western Alaska. (
  • S wine influenza has evolved from a seasonal disease caused by a stable genotype of swine influenza virus (SIV) to a year-round, endemic respiratory disease caused by multiple SIV genotypes undergoing continuous change. (
  • The S-OIV will continue to mutate in unknown ways over the coming months and might even replace H1 virus as the seasonal flu virus, evolving new antigenic variants every year, the journal speculated. (
  • Antigenic drift causes small, incremental changes in the virus over time. (
  • Drift is the standard evolutionary process of influenza viruses, and often come about due to replication errors that are common with single-strand RNA viruses (see NIAID Video: Antigenic Drift ). (
  • Serological assays based on hemagglutination inhibition (HI) are historically the most common way to determine antigenic characteristics of influenza A viruses, and the HI test also serves as a functional assay for detection of anti-influenza antibodies in sera. (
  • Hemagglutination reactions are compared among the sets of antisera and viral antigens in a test panel, and assumptions are made concerning the antigenic relatedness of the viruses on the basis of these HI reactions. (
  • Machine learning prediction and experimental validation of antigenic drift in H3 influenza A viruses in swine. (
  • Production of reassortant viruses containing human rotavirus VP4 and SA11 VP7 for measuring neutralizing antibody following natural infection. (
  • In order to measure neutralizing antibody responses to VP4 and VP7 separately, reassortants bearing VP4 of each of the major human rotavirus P types with VP7 of SA11 origin were successfully produced by neutralizing monoclonal antibody selection. (
  • Despite the continuous circulation of these subtypes for several years, no natural reassortant has been detected so far among the domestic poultry population in Egypt. (
  • However, H1 viruses have continued to be more prevalent and more genetically diverse than H3 viruses in the U.S. swine population. (
  • Across two sets of replica experiments we infer multiple alleles to be under selection, including variants associated with receptor binding specificity, glycosylation, and with the increased transmissibility of the virus. (
  • However, their transmissibility by respiratory droplets was related to their HA and NA lineages: TRS viruses with human-like HA and NA were transmitted most efficiently, those with swine-like HA and NA were transmitted minimally or not transmitted, and those with swine-like HA and human-like NA (N2) showed intermediate transmissibility. (
  • We conclude that the lineages of HA and NA may play a crucial role in the respiratory droplet transmissibility of these viruses. (
  • Similarly, detections of HP IAVs in wild birds and domestic poultry occurred repeatedly in North America during winter and spring of 2015, but tapered off by summer, raising the possibility that migratory birds could disperse viruses to northerly breeding areas where they may be maintained to eventually seed future poultry outbreaks as birds migrate back to wintering grounds. (
  • The viral haemagglutinin (HA) protein is a known host-range determinant as it mediates virus binding to host-specific cellular receptors. (
  • According to the International Committee on Taxonomy of Viruses [ 5 ], the genus Phlebovirus includes ten viral species in the Old World and the Americas. (
  • The availability of complete genome sequence data facilitates the accurate detection, identification and diagnosis of viruses and viral infections, and this is especially true for viruses with segmented genomes because it can be difficult or even impossible to differentiate between reassortants and their precursors when incomplete sequence data are available. (
  • Simultaneously, a similar virus was also detected in Canadian mink based on partial viral genome sequencing. (
  • When a complete virus particle ( virion ) comes in contact with a host cell, only the viral nucleic acid and, in some viruses, a few enzymes are injected into the host cell. (
  • Some of these may already have been present within the initial virus, and others may be coded for by the viral genome for production within the host cell. (
  • For certain viruses the RNA is replicated by a viral enzyme ( transcriptase ) contained in the virion, or produced by the host cell using the viral RNA as a messenger. (
  • In viruses that have membranes, membrane-bound viral proteins are synthesized by the host cell and move, like host cell membrane proteins, to the cell surface. (
  • Parsimony analyses of viral phylogeography suggest that the reassortant viruses may have originated from greater Jakarta and surroundings, and subsequently spread to other regions in the West Java province. (
  • A novel cause of chronic viral meningoencephalitis: Cache Valley virus. (
  • A hierarchical model-selection procedure is used to infer the underlying fitness landscape of the virus insofar as that landscape is explored by the viral population. (
  • Infectious bursal disease virus (IBDV) is one of the most important immunosuppressive viral agents in poultry production. (
  • Viral architecture is very complex, but every virus contains at least a genome and a capsid. (
  • Creation of a swine reverse genetics influenza virus system for evaluation of viral bacterial pathogenesis, SSOM Research Committee. (
  • Also in November 2014, a novel H5N2 virus was reported in outbreaks on chicken and turkey farms in Fraser Valley, British Columbia, Canada. (
  • This H5N2 influenza virus is a reassortant. (
  • Whole- genome sequencing indicated the virus was highly similar to the H5N2 reassortant virus from Canada. (
  • An avian influenza virus A(H7N9) reassortant that recently emerged in the United States with low pathogenic phenotype does not efficiently infect swine. (
  • Emerging H7N9 virus easily jumps between ferrets even though there is no evidence for human-to-human transmission. (
  • Since the notification of a novel reassortant influenza A(H7N9) virus on 31 March 2013, 1 548 laboratory-confirmed cases of human infection with avian influenza A(H7N9) virus have been reported. (
  • This fourth update of the risk assessment on human infection with avian influenza A(H7N9) virus, summarises the epidemiological and virological information on the disease in China and Canada, and assesses the risk to public health in the EU/EEA and to EU/EEA citizens. (
  • Emerging H7N9 influenza A (novel reassortant avian-origin) pneumonia: radiologic findings. (
  • Twelve patients (nine men and three women) with novel avian-origin influenza A H7N9 virus infection were enrolled. (
  • One of the reassortants also contained the 1918 nonstructural (NS1) protein, an inhibitor of the host interferon response. (
  • Morens D, Taubenberger J and Fauci A (2009) The Persistent Legacy of the 1918 influenza virus. (
  • The virus isolation was conducted on 10-day-old SPF embryonated eggs using the chorioallantoic membrane route (CAM) [ 20 ]. (
  • virus subtypes have the potential to the Kimura 2-parameter method ( 12 ). (
  • Group 2 influenza viruses have not been detected since the end of 2014, whereas Group 1 influenza viruses have continually evolved and reassorted with the "gene pool" circulating in south China, resulting in the rise of novel subtypes of this influenza virus. (
  • They recommend monitoring for human adaptation markers on both avian and human viruses during avian flu outbreaks. (
  • Detections of HP viruses in wild birds in the contiguous United States and southern Canadian provinces continued into winter and spring of 2015 raising concerns that migratory birds could potentially disperse viruses to more northerly breeding areas where they could be maintained to eventually seed future poultry outbreaks. (
  • Some of the most virulent diseases are caused by viruses, e.g., the hemorrhagic fever caused by Ebola virus. (
  • We don't yet know how virulent infections with this virus are because there aren't enough cases to make that judgment. (
  • Considering that novel reassorted H6N6 viruses were isolated from chickens in this study, it is possible that these chickens play an important role in the generation of novel reassorted H6N6 AIVs, and these results emphasize the need for continued surveillance of the H6N6 AIVs circulating in poultry. (
  • The virus is also highly pathogenic for poultry as defined by the World Organization for Animal Health ( 4 ). (
  • We propose active surveillance to support prevention of spread of the virus, and in areas where infection is documented, culling of wild birds and infected poultry, especially domestic ducks. (
  • Double reassortant H13N8 influenza A virus was isolated from gull in Mongolia. (
  • A case of reassortant seasonal influenza. (
  • Seasonal influenza vaccination is important to decrease the risk of getting infected with human seasonal influenza viruses, which are beginning to circulate in the United States for the 2011-2012 season. (
  • The antiviral drugs oseltamivir and zanamivir - which are used to treat infection with human seasonal viruses - also have shown activity against swine-origin viruses. (
  • New viruses are then released either by destroying their host cell or by forming small buds that break off and infect other cells. (
  • Avian influenza viruses primarily infect birds now, but these viruses constantly change, or mutate. (
  • DNA barcoding techniques for avian influenza virus surveillance in migratory bird habitats. (
  • Although research on the origins and epidemiology of these infections is ongoing, the most likely route of infection for the whooper swans was through direct or indirect contact with reassortant viruses shed by migratory wild birds in Korea. (
  • In addition, constant monitoring of AIVs in migratory birds is essential in the early detection of influenza virus introduction into Egypt. (
  • Avian influenza viruses (AIVs) have been identified from more than 100 different species of wild birds around the globe. (
  • Intervention control strategies should be performed to minimize the possible contact of domestic birds with wild birds to lower the risk of virus transmission at this interface. (
  • Wild birds in orders Anseriformes (ducks, geese, swans) and Charadriiformes (gulls, terns, shore birds) are the natural reservoirs of avian influenza viruses ( 1 , 2 ). (
  • Low pathogenic avian influenza (LPAI) viruses usually trigger milder and primarily respiratory disease in birds. (
  • Though rare, human infections with swine-origin influenza viruses can occur, usually after close contact with infected swine. (