Influenza, Human: 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.Influenza A 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.Influenza A Virus, H1N1 Subtype: 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.Influenza A Virus, H5N1 Subtype: 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.Influenza Vaccines: 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.Influenza in Birds: 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.Influenza A Virus, H3N2 Subtype: 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.Hemagglutinin Glycoproteins, Influenza Virus: 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.Influenza B virus: Species of the genus INFLUENZAVIRUS B that cause HUMAN INFLUENZA and other diseases primarily in humans. Antigenic variation is less extensive than in type A viruses (INFLUENZA A VIRUS) and consequently there is no basis for distinct subtypes or variants. Epidemics are less likely than with INFLUENZA A VIRUS and there have been no pandemics. Previously only found in humans, Influenza B virus has been isolated from seals which may constitute the animal reservoir from which humans are exposed.Orthomyxoviridae Infections: Virus diseases caused by the ORTHOMYXOVIRIDAE.Vaccinia virus: 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.RNA Viruses: Viruses whose genetic material is RNA.Influenza A Virus, H9N2 Subtype: 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.Orthomyxoviridae: A family of RNA viruses causing INFLUENZA and other diseases. There are five recognized genera: INFLUENZAVIRUS A; INFLUENZAVIRUS B; INFLUENZAVIRUS C; ISAVIRUS; and THOGOTOVIRUS.Receptors, Virus: 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.Virus Replication: 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.Influenza A Virus, H7N9 Subtype: 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.Virus Cultivation: Process of growing viruses in live animals, plants, or cultured cells.Hemagglutinins, Viral: Specific hemagglutinin subtypes encoded by VIRUSES.Virus Shedding: 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).Birds: Warm-blooded VERTEBRATES possessing FEATHERS and belonging to the class Aves.Hemagglutination Inhibition Tests: 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.Virus Diseases: A general term for diseases produced by viruses.Neuraminidase: 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)Simian virus 40: A species of POLYOMAVIRUS originally isolated from Rhesus monkey kidney tissue. It produces malignancy in human and newborn hamster kidney cell cultures.Virus Assembly: The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Defective Viruses: 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.Plant Viruses: Viruses parasitic on plants higher than bacteria.DNA Viruses: Viruses whose nucleic acid is DNA.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.Viral Proteins: Proteins found in any species of virus.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Influenza A Virus, H7N7 Subtype: 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.Sindbis Virus: 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.Measles virus: The type species of MORBILLIVIRUS and the cause of the highly infectious human disease MEASLES, which affects mostly children.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Pandemics: Epidemics of infectious disease that have spread to many countries, often more than one continent, and usually affecting a large number of people.Genes, Viral: The functional hereditary units of VIRUSES.Rabies virus: 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.Antiviral Agents: 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.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Molecular Sequence Data: 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.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Influenza A Virus, H3N8 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 3 and neuraminidase 8. The H3N8 subtype has frequently been found in horses.Respiratory Syncytial Viruses: 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.Influenza A Virus, H5N2 Subtype: 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.Hepatitis B virus: 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.West Nile virus: 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.Influenza A Virus, H7N1 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 7 and neuraminidase 1. This subtype has demonstrated the ability to mutate from a low pathogenic form to a highly pathogenic form in birds. It was responsible for a 1999 outbreak in turkeys in Italy.Chickens: 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.Virus Activation: The mechanism by which latent viruses, such as genetically transmitted tumor viruses (PROVIRUSES) or PROPHAGES of lysogenic bacteria, are induced to replicate and then released as infectious viruses. It may be effected by various endogenous and exogenous stimuli, including B-cell LIPOPOLYSACCHARIDES, glucocorticoid hormones, halogenated pyrimidines, IONIZING RADIATION, ultraviolet light, and superinfecting viruses.Vesicular stomatitis Indiana virus: 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.Influenza A Virus, H2N2 Subtype: 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.Influenza A Virus, H1N2 Subtype: 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.Oseltamivir: An acetamido cyclohexene that is a structural homolog of SIALIC ACID and inhibits NEURAMINIDASE.Amino Acid Sequence: 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.Dogs: 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)Neutralization Tests: 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).Vero Cells: A CELL LINE derived from the kidney of the African green (vervet) monkey, (CERCOPITHECUS AETHIOPS) used primarily in virus replication studies and plaque assays.Virus Latency: 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.Cercopithecus aethiops: 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.Virion: 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.DucksVaccination: Administration of vaccines to stimulate the host's immune response. This includes any preparation intended for active immunological prophylaxis.Viral Plaque Assay: 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.Oncogenic Viruses: Viruses that produce tumors.Simian immunodeficiency virus: 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.Parainfluenza Virus 1, Human: A species of RESPIROVIRUS also called hemadsorption virus 2 (HA2), which causes laryngotracheitis in humans, especially children.Virus Attachment: 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.Seasons: Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Mumps virus: The type species of RUBULAVIRUS that causes an acute infectious disease in humans, affecting mainly children. Transmission occurs by droplet infection.Mosaic Viruses: Viruses which produce a mottled appearance of the leaves of plants.Semliki forest virus: A species of ALPHAVIRUS isolated in central, eastern, and southern Africa.DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.Chick Embryo: 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.Hepatitis A virus: 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.Virus Inactivation: 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.Avian Sarcoma Viruses: Group of alpharetroviruses (ALPHARETROVIRUS) producing sarcomata and other tumors in chickens and other fowl and also in pigeons, ducks, and RATS.Ferrets: 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.BK Virus: 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.Vaccines, Inactivated: 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.Gene Expression Regulation, Viral: Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses.Tumor Virus Infections: 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.JC Virus: 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.Viruses, Unclassified: Viruses whose taxonomic relationships have not been established.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Respiratory Syncytial Virus Infections: Pneumovirus infections caused by the RESPIRATORY SYNCYTIAL VIRUSES. Humans and cattle are most affected but infections in goats and sheep have been reported.Madin Darby Canine Kidney Cells: An epithelial cell line derived from a kidney of a normal adult female dog.Avian leukosis virus: The type species of ALPHARETROVIRUS producing latent or manifest lymphoid leukosis in fowl.Sendai virus: The type species of RESPIROVIRUS in the subfamily PARAMYXOVIRINAE. It is the murine version of HUMAN PARAINFLUENZA VIRUS 1, distinguished by host range.Vaccines, Attenuated: 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.Viral Core Proteins: Proteins found mainly in icosahedral DNA and RNA viruses. They consist of proteins directly associated with the nucleic acid inside the NUCLEOCAPSID.Virulence: 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.Poultry: Domesticated birds raised for food. It typically includes CHICKENS; TURKEYS, DUCKS; GEESE; and others.Amantadine: An antiviral that is used in the prophylactic or symptomatic treatment of influenza A. It is also used as an antiparkinsonian agent, to treat extrapyramidal reactions, and for postherpetic neuralgia. The mechanisms of its effects in movement disorders are not well understood but probably reflect an increase in synthesis and release of dopamine, with perhaps some inhibition of dopamine uptake.Cytopathogenic Effect, Viral: 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.Bluetongue virus: The type species of ORBIVIRUS causing a serious disease in sheep, especially lambs. It may also infect wild ruminants and other domestic animals.Reassortant Viruses: 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.Virology: The study of the structure, growth, function, genetics, and reproduction of viruses, and VIRUS DISEASES.Respiratory Syncytial Virus, Human: 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.Capsid: The outer protein protective shell of a virus, which protects the viral nucleic acid.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Moloney murine leukemia virus: 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.Virus Integration: 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.HIV Infections: Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).Cells, Cultured: 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.Cross Reactions: Serological reactions in which an antiserum against one antigen reacts with a non-identical but closely related antigen.Simplexvirus: A genus of the family HERPESVIRIDAE, subfamily ALPHAHERPESVIRINAE, consisting of herpes simplex-like viruses. The type species is HERPESVIRUS 1, HUMAN.Recombination, Genetic: 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.Yellow fever virus: The type species of the FLAVIVIRUS genus. Principal vector transmission to humans is by AEDES spp. mosquitoes.Genetic Vectors: DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Influenza A Virus, H7N3 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 7 and neuraminidase 3. It was first detected in turkeys in Britain in 1963 and there have been several outbreaks on poultry farms since that time. A couple cases of human infections have been reported.Tobacco Mosaic Virus: The type species of TOBAMOVIRUS which causes mosaic disease of tobacco. Transmission occurs by mechanical inoculation.RNA Replicase: 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)Nucleoproteins: Proteins conjugated with nucleic acids.Myxoma virus: The type species of LEPORIPOXVIRUS causing infectious myxomatosis, a severe generalized disease, in rabbits. Tumors are not always present.Cowpox virus: A species of ORTHOPOXVIRUS that is the etiologic agent of COWPOX. It is closely related to but antigenically different from VACCINIA VIRUS.Variola virus: 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.Viral Load: The quantity of measurable virus in a body fluid. Change in viral load, measured in plasma, is sometimes used as a SURROGATE MARKER in disease progression.Lassa virus: 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.Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.Drug Resistance, Viral: The ability of viruses to resist or to become tolerant to chemotherapeutic agents or antiviral agents. This resistance is acquired through gene mutation.Host-Pathogen Interactions: The interactions between a host and a pathogen, usually resulting in disease.Virus Physiological Phenomena: Biological properties, processes, and activities of VIRUSES.Parainfluenza Virus 3, Human: A species of RESPIROVIRUS frequently isolated from small children with pharyngitis, bronchitis, and pneumonia.Hepacivirus: A genus of FLAVIVIRIDAE causing parenterally-transmitted HEPATITIS C which is associated with transfusions and drug abuse. Hepatitis C virus is the type species.Chikungunya virus: A species of ALPHAVIRUS causing an acute dengue-like fever.Norwalk virus: 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.Encephalitis Viruses: 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.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Epstein-Barr Virus Infections: Infection with human herpesvirus 4 (HERPESVIRUS 4, HUMAN); which may facilitate the development of various lymphoproliferative disorders. These include BURKITT LYMPHOMA (African type), INFECTIOUS MONONUCLEOSIS, and oral hairy leukoplakia (LEUKOPLAKIA, HAIRY).Herpesvirus 1, Human: 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.Species Specificity: 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.DNA Virus InfectionsInfluenzavirus C: A genus of the family ORTHOMYXOVIRIDAE comprising viruses similar to types A and B but less common, more stable, more homogeneous, and lacking the neuraminidase protein. They have not been associated with epidemics but may cause mild influenza. Influenza C virus is the type species.Swine: 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).Herpesvirus 4, Human: The type species of LYMPHOCRYPTOVIRUS, subfamily GAMMAHERPESVIRINAE, infecting B-cells in humans. It is thought to be the causative agent of INFECTIOUS MONONUCLEOSIS and is strongly associated with oral hairy leukoplakia (LEUKOPLAKIA, HAIRY;), BURKITT LYMPHOMA; and other malignancies.Viral Structural Proteins: 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).HIV-1: The type species of LENTIVIRUS and the etiologic agent of AIDS. It is characterized by its cytopathic effect and affinity for the T4-lymphocyte.Encephalitis Viruses, Tick-Borne: A subgroup of the genus FLAVIVIRUS that causes encephalitis and hemorrhagic fevers and is found in eastern and western Europe and the former Soviet Union. It is transmitted by TICKS and there is an associated milk-borne transmission from viremic cattle, goats, and sheep.Pneumonia, Viral: Inflammation of the lung parenchyma that is caused by a viral infection.Antibodies, Neutralizing: Antibodies that reduce or abolish some biological activity of a soluble antigen or infectious agent, usually a virus.Leukemia Virus, Feline: A species of GAMMARETROVIRUS causing leukemia, lymphosarcoma, immune deficiency, or other degenerative diseases in cats. Several cellular oncogenes confer on FeLV the ability to induce sarcomas (see also SARCOMA VIRUSES, FELINE).Capsid Proteins: Proteins that form the CAPSID of VIRUSES.Cross Protection: Protection conferred on a host by inoculation with one strain or component of a microorganism that prevents infection when later challenged with a similar strain. Most commonly the microorganism is a virus.Foot-and-Mouth Disease Virus: The type species of APHTHOVIRUS, causing FOOT-AND-MOUTH DISEASE in cloven-hoofed animals. Several different serotypes exist.Epitopes: Sites on an antigen that interact with specific antibodies.Porcine respiratory and reproductive syndrome virus: A species of ARTERIVIRUS causing reproductive and respiratory disease in pigs. The European strain is called Lelystad virus. Airborne transmission is common.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.RNA Virus InfectionsSwine Diseases: Diseases of domestic swine and of the wild boar of the genus Sus.Hepatitis Viruses: Any of the viruses that cause inflammation of the liver. They include both DNA and RNA viruses as well viruses from humans and animals.Hemagglutination, Viral: Agglutination of ERYTHROCYTES by a virus.Poultry Diseases: 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.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Genetic Variation: Genotypic differences observed among individuals in a population.Zanamivir: A guanido-neuraminic acid that is used to inhibit NEURAMINIDASE.Mice, Inbred BALB CHuman T-lymphotropic virus 1: A strain of PRIMATE T-LYMPHOTROPIC VIRUS 1 isolated from mature T4 cells in patients with T-lymphoproliferation malignancies. It causes adult T-cell leukemia (LEUKEMIA-LYMPHOMA, T-CELL, ACUTE, HTLV-I-ASSOCIATED), T-cell lymphoma (LYMPHOMA, T-CELL), and is involved in mycosis fungoides, SEZARY SYNDROME and tropical spastic paraparesis (PARAPARESIS, TROPICAL SPASTIC).Satellite Viruses: Defective viruses which can multiply only by association with a helper virus which complements the defective gene. Satellite viruses may be associated with certain plant viruses, animal viruses, or bacteriophages. They differ from satellite RNA; (RNA, SATELLITE) in that satellite viruses encode their own coat protein.Oncolytic Viruses: Tumor-selective, replication competent VIRUSES that have antineoplastic effects. This is achieved by producing cytotoxicity-enhancing proteins and/or eliciting an antitumor immune response. They are genetically engineered so that they can replicate in CANCER cells but not in normal cells, and are used in ONCOLYTIC VIROTHERAPY.Enzyme-Linked Immunosorbent Assay: An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.Orf virus: The type species of PARAPOXVIRUS which causes a skin infection in natural hosts, usually young sheep. Humans may contract local skin lesions by contact. The virus apparently persists in soil.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Diarrhea Viruses, Bovine Viral: A group of viruses in the genus PESTIVIRUS, causing diarrhea, fever, oral ulcerations, hemorrhagic syndrome, and various necrotic lesions among cattle and other domestic animals. The two species (genotypes), BVDV-1 and BVDV-2 , exhibit antigenic and pathological differences. The historical designation, BVDV, consisted of both (then unrecognized) genotypes.Hepatitis E virus: A positive-stranded RNA virus species in the genus HEPEVIRUS, causing enterically-transmitted non-A, non-B hepatitis (HEPATITIS E).Cell Transformation, Viral: An inheritable change in cells manifested by changes in cell division and growth and alterations in cell surface properties. It is induced by infection with a transforming virus.Hepatitis C: INFLAMMATION of the LIVER in humans caused by HEPATITIS C VIRUS, a single-stranded RNA virus. Its incubation period is 30-90 days. Hepatitis C is transmitted primarily by contaminated blood parenterally, and is often associated with transfusion and intravenous drug abuse. However, in a significant number of cases, the source of hepatitis C infection is unknown.Haplorhini: A suborder of PRIMATES consisting of six families: CEBIDAE (some New World monkeys), ATELIDAE (some New World monkeys), CERCOPITHECIDAE (Old World monkeys), HYLOBATIDAE (gibbons and siamangs), CALLITRICHINAE (marmosets and tamarins), and HOMINIDAE (humans and great apes).Friend murine leukemia virus: A strain of Murine leukemia virus (LEUKEMIA VIRUS, MURINE) producing leukemia of the reticulum-cell type with massive infiltration of liver, spleen, and bone marrow. It infects DBA/2 and Swiss mice.Amino Acid Substitution: The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.Mammary Tumor Virus, Mouse: The type species of BETARETROVIRUS commonly latent in mice. It causes mammary adenocarcinoma in a genetically susceptible strain of mice when the appropriate hormonal influences operate.Hemagglutinins: Agents that cause agglutination of red blood cells. They include antibodies, blood group antigens, lectins, autoimmune factors, bacterial, viral, or parasitic blood agglutinins, etc.Respirovirus: A genus of the family PARAMYXOVIRIDAE (subfamily PARAMYXOVIRINAE) where all the virions have both HEMAGGLUTININ and NEURAMINIDASE activities and encode a non-structural C protein. SENDAI VIRUS is the type species.Viral Interference: A phenomenon in which infection by a first virus results in resistance of cells or tissues to infection by a second, unrelated virus.Viral Fusion Proteins: Proteins, usually glycoproteins, found in the viral envelopes of a variety of viruses. They promote cell membrane fusion and thereby may function in the uptake of the virus by cells.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Sarcoma Viruses, Murine: A group of replication-defective viruses, in the genus GAMMARETROVIRUS, which are capable of transforming cells, but which replicate and produce tumors only in the presence of Murine leukemia viruses (LEUKEMIA VIRUS, MURINE).Fowlpox virus: The type species of the genus AVIPOXVIRUS. It is the etiologic agent of FOWLPOX.Archaeal Viruses: Viruses whose hosts are in the domain ARCHAEA.Bird Diseases: Diseases of birds not considered poultry, therefore usually found in zoos, parks, and the wild. The concept is differentiated from POULTRY DISEASES which is for birds raised as a source of meat or eggs for human consumption, and usually found in barnyards, hatcheries, etc.Open Reading Frames: A sequence of successive nucleotide triplets that are read as CODONS specifying AMINO ACIDS and begin with an INITIATOR CODON and end with a stop codon (CODON, TERMINATOR).Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Leukemia Virus, Bovine: The type species of DELTARETROVIRUS that causes a form of bovine lymphosarcoma (ENZOOTIC BOVINE LEUKOSIS) or persistent lymphocytosis.Sentinel Surveillance: Monitoring of rate of occurrence of specific conditions to assess the stability or change in health levels of a population. It is also the study of disease rates in a specific cohort such as in a geographic area or population subgroup to estimate trends in a larger population. (From Last, Dictionary of Epidemiology, 2d ed)RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Fluorescent Antibody Technique: Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.HIV: Human immunodeficiency virus. A non-taxonomic and historical term referring to any of two species, specifically HIV-1 and/or HIV-2. Prior to 1986, this was called human T-lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV). From 1986-1990, it was an official species called HIV. Since 1991, HIV was no longer considered an official species name; the two species were designated HIV-1 and HIV-2.Vaccines, Synthetic: Small synthetic peptides that mimic surface antigens of pathogens and are immunogenic, or vaccines manufactured with the aid of recombinant DNA techniques. The latter vaccines may also be whole viruses whose nucleic acids have been modified.Lymphocytic choriomeningitis virus: The type species of ARENAVIRUS, part of the Old World Arenaviruses (ARENAVIRUSES, OLD WORLD), producing a silent infection in house and laboratory mice. In humans, infection with LCMV can be inapparent, or can present with an influenza-like illness, a benign aseptic meningitis, or a severe meningoencephalomyelitis. The virus can also infect monkeys, dogs, field mice, guinea pigs, and hamsters, the latter an epidemiologically important host.Respiratory Tract Infections: Invasion of the host RESPIRATORY SYSTEM by microorganisms, usually leading to pathological processes or diseases.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Hendra Virus: A species of HENIPAVIRUS first identified in Australia in 1994 in HORSES and transmitted to humans. The natural host appears to be fruit bats (PTEROPUS).Serial Passage: Inoculation of a series of animals or in vitro tissue with an infectious bacterium or virus, as in VIRULENCE studies and the development of vaccines.Influenza A Virus, H7N2 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 7 and neuraminidase 2. It has been involved in a number of outbreaks in the 21st century on poultry farms and has been isolated a few times in humans.Gene Products, gag: Proteins coded by the retroviral gag gene. The products are usually synthesized as protein precursors or POLYPROTEINS, which are then cleaved by viral proteases to yield the final products. Many of the final products are associated with the nucleoprotein core of the virion. gag is short for group-specific antigen.
Twenty were confirmed to be linked to a new strain of Influenza A virus subtype H1N1. "'As many as 23,000 Mexicans were likely ... Researchers plan to go to Mexico, where the viruses in 12 cases match six in the U.S". Los Angeles Times. "US Declares Public ... Influenza: H1N1 at Curlie (based on DMOZ) Swine influenza, at the World Health Organization WHO's current Pandemic Influenza ... June 2009). "Emergence of a novel swine-origin influenza A (H1N1) virus in humans". N. Engl. J. Med. 360 (25): 2605-15. doi: ...
Influenza vaccine Influenza A virus subtype H3N2 Paul, William E. Fundamental Immunology. p. 1273. "World health group issues ... and direct transmission of avian viruses to humans is possible. H1N1 may have been transmitted directly from birds to humans ( ... cross-immunity within and between subtypes of influenza is poorly understood. "Three strains of Hong Kong influenza virus ... Both the H2N2 and H3N2 pandemic flu strains contained genes from avian influenza viruses. The new subtypes arose in pigs ...
... influenza virus and tuberculosis; or specific strains such as H1N1 virus. Genetic identification can be swift; for example a ... "RT-PCR/electrospray ionization mass spectrometry approach in detection and characterization of influenza viruses". Expert ... Molecular diagnostics can help diagnose the subtype-for example of infections and cancers-or the genetic analysis of a disease ... Burkardt, H. J. (2011). "Pandemic H1N1 2009 ('swine flu'): Diagnostic and other challenges". Expert Review of Molecular ...
... for emergency use in the treatment of patients hospitalized with influenza during the 2009-10 influenza A virus subtype H1N1 ... BCX4430 is an RNA dependent-RNA polymerase inhibitor that has demonstrated broad-spectrum activity for multiple viruses. ... Peramivir is an intravenous (i.v.) antiviral drug being developed for the treatment of influenza. BioCryst expects to file for ...
... of the 1918 virus and subsequent human viruses differ by only 10 amino acids from the avian influenza viruses. Viruses with ... a subtype of avian strain H1N1, had been reconstructed using historic tissue samples and a small part of the RNA from a modern ... Influenza viruses have a relatively high mutation rate that is characteristic of RNA viruses. The H5N1 virus has mutated into a ... Both the H2N2 and H3N2 pandemic strains contained avian flu virus RNA segments. "While the pandemic human influenza viruses of ...
... this certain antiviral protein defended cells from viruses such as influenza (including influenza A virus subtype H1N1), West ... in this antiviral protein and also how severe a person reacts to certain viruses like influenza or the more dangerous H1N1 ... that may increase their risk of contracting severe influenza virus infection. Houghton Mifflin Company. American Heritage ... specifically the Moloney murine leukemia virus (MLV) and the Sindbis virus (SIN). ZAP prevents the viral mRNA from building up ...
"Evaluation of MChip with Historic Subtype H1N1 Influenza A Viruses, Including the 1918 "Spanish Flu" Strain". Journal of ... The overall pattern of fluorescence intensities were utilized to type and subtype the influenza virus(es) present. various ... Numerous short DNA capture sequences were designed , and used to both type and subtype influenza A viruses by taking advantage ... focusing on the ability to discriminate human H1N1, human H3N2, and avian influenza (H5N1) subtypes, and resulted in high ...
... coordinated with Emory Vaccine Center of Emory University on a program of drug development for Influenza A virus subtype H1N1 ... Known for his studies on papilloma viruses, Pillai is an elected fellow of the Indian Academy of Sciences, National Academy of ...
... with 20 confirmed to be linked to a new swine influenza strain of Influenza A virus subtype H1N1. As of April 26 there had been ... Researchers plan to go to Mexico, where the viruses in 12 cases match six in the U.S". Los Angeles Times. "US Declares Public ... These included one seasonal influenza A (H1N1), 13 influenza A (H3N2), 23 Influenza B, and 1, 855 2009 influenza A (H1n1) virus ... The 2009 flu pandemic in North America, part of an epidemic in 2009 of a new strain of influenza A virus subtype H1N1 causing ...
The 2009 flu pandemic in Oceania, part of an epidemic in 2009 of a new strain of influenza A virus subtype H1N1 causing what ... and approximately 100 deaths a year directly attributed to influenza viruses. As of July 21, there were 2,255 confirmed cases ... "Influenza A (H1N1) Swine Flu - Update 110". Archived from the original on 2009-09-11. Retrieved 2009-07-22. "Palau on health ... A multi-sectoral task force has been activated by the Solomon Islands Ministry of Health to deal with the swine influenza virus ...
... in particular influenza viruses including elucidating the origin of the influenza A virus subtype H1N1. Dr. Rabadán's work in ... Trifonov, V., Khiabanian, H., Greenbaum, B. & Rabadan, R. The origin of the recent swine influenza A(H1N1) virus infecting ... and origins of the 2009 influenza A (H1N1) virus. N Engl J Med 361, 115-119, doi:10.1056/NEJMp0904572 (2009). Tiacci, E. et al ... Rabadán's current interest focuses on uncovering patterns of evolution in biological systems-in particular, RNA viruses and ...
... along with H5 viruses that are now regarded as the most likely novel influenza subtypes to cause a pandemic. Guan has defined ... evolutionary history and development of the 2009 H1N1 pandemic virus and revealed the genesis, infection source, evolutionary ... In early 2017, Guan warned that the H7N9 influenza virus "poses the greatest threat to humanity than any other in the past 100 ... for his influenza virus research work. Guan's publication record contained in the United States National Institutes of Health ...
The Pandemic H1N1/09 virus is a swine origin Influenza A virus subtype H1N1 virus strain responsible for the 2009 flu pandemic ... North American swine influenza, North American avian influenza, human influenza, and two swine influenza viruses typically ... In July 2009, WHO experts named the virus "pandemic H1N1/09 virus" to distinguish it from both various seasonal H1N1 virus ... North American swine influenza, North American avian influenza, human influenza, and swine influenza virus typically found in ...
... with 20 confirmed to be linked to a new swine influenza strain of Influenza A virus subtype H1N1. As of April 26 there have ... "CDC: Swine flu viruses in U.S. and Mexico match". CNN. April 25, 2009. Archived from the original on April 26, 2009. Retrieved ... The new strain was identified as a combination of several different strains of Influenzavirus A, subtype H1N1, including ... Secretaria de Salud, Mexico "Outbreak of Swine-Origin Influenza A (H1N1) Virus Infection - Mexico, March-April 2009" - CDC ...
... was a category 5 influenza pandemic caused by an unusually severe and deadly Influenza A virus strain of subtype H1N1. The ... The 1977 virus was similar to other A/H1N1 viruses that had circulated prior to 1957. The virus was included in the 1978-79 ... Typically this vaccine includes material from two influenza A virus subtypes and one influenza B virus strain. A vaccine ... "Human influenza virus" usually refers to those subtypes that spread widely among humans. H1N1, H1N2, and H3N2 are the only ...
... is caused by influenza A subtypes H1N1, H1N2, H2N3, H3N1, and H3N2. In pigs, four influenza A virus subtypes ( ... Swine influenza virus (SIV) or swine-origin influenza virus (S-OIV) is any strain of the influenza family of viruses that is ... A triple reassortment event in a pig host of North American H1N1 swine virus, the human H3N2 virus and avian H1N1 virus ... Influenza B and C viruses are almost exclusively isolated from man, although influenza C virus has also been isolated from pigs ...
Influenza viruses are characterized by the type of HA and NA that they carry; hence H1N1, H5N2 etc. A highly pathogenic avian ... March 2005). "Characterization of a Novel Influenza A Virus Hemagglutinin Subtype (H16) Obtained from Black-Headed Gulls". J. ... These subtypes are named H1 through H18. H16 was discovered in 2004 on influenza A viruses isolated from black-headed gulls ... Influenza hemagglutinin (HA) or haemagglutinin (British English) is a glycoprotein found on the surface of influenza viruses. ...
... and 84 novel influenza A (H1N1) viruses. All 947 influenza seasonal A (H1) viruses are related to the influenza A (H1N1) ... Influenza A virus subtype H3N2 (A/H3N2) is a subtype of viruses that causes influenza (flu). H3N2 viruses can infect birds and ... H1N1) reference virus selected by WHO as a potential candidate for novel influenza A (H1N1) vaccine. Influenza B viruses ... A 2007 study reported: "In swine, three influenza A virus subtypes (H1N1, H3N2, and H1N2) are circulating throughout the world ...
... was an unusually deadly influenza pandemic, the first of the two pandemics involving H1N1 influenza virus.[1] It infected 500 ... Both the H2N2 and H3N2 pandemic strains contained avian flu virus RNA segments. "While the pandemic human influenza viruses of ... An effort to recreate the 1918 flu strain (a subtype of avian strain H1N1) was a collaboration among the Armed Forces Institute ... Spanish Influenza in North America, 1918-1919. *1918 Influenza Virus and memory B-cells - Exposure to virus generates lifelong ...
Influenza A viruses can be further classified into subtypes, such as A/H1N1 and A/H3N2. Here, subtypes are denoted according to ... Oxburgh, L.; Klingeborn, B. (1999). "Cocirculation of two distinct lineages of equine influenza virus subtype H3N8". Journal of ... Influenza viruses circulate in other species as well, most notably as swine influenza and avian influenza. Through reassortment ... Human influenza is an acute respiratory infection primarily caused by viruses influenza A and influenza B. ...
Serotypes or Subtypes Hosts Influenza virus A Influenza A virus* H1N1, H1N2, H2N2, H3N1, H3N2, H3N8, H5N1, H5N2, H5N3, H5N8, ... Mammalian influenza viruses tend to be labile, but can survive several hours in mucus.[55] Avian influenza virus can survive ... It includes seven genera: Influenzavirus A, Influenzavirus B, Influenzavirus C, Influenzavirus D, Isavirus, Thogotovirus, and ... Influenza CEdit. Main article: Influenzavirus C. The influenza C virus infects humans and pigs, and can cause severe illness ...
Influenza viruses that are normally found in swine are known as swine influenza viruses (SIVs). The known SIV strains include ... Influenza A (H1N1) virus is the subtype of influenza A virus that was the most common cause of human influenza (flu) in 2009, ... North American swine influenza, North American avian influenza, human influenza, and swine influenza virus typically found in ... This colorized transmission electron micrograph shows H1N1 influenza virus particles. Surface proteins on the virus particles ...
... virus designation of H7N9 identifies it as having HA of the H7 subtype and NA of the N9 subtype. Avian influenza A H7 viruses ... H1N1)pdm09 vaccines [about 60% to 70% effectiveness], particularly with regard to vaccine efficacy in persons older than 65 ... H7N9 is a bird flu strain of the species Influenza virus A (avian influenza virus or bird flu virus). Avian influenza A H7 ... Influenza A viruses are divided into subtypes based on two proteins on the surface of the virus: hemagglutinin (HA) and ...
... subtypes. Because the hemagglutinin protein of the virus is similar to that of the currently[when?] circulating A(H1N1) viruses ... H1N1, H1N2, and H3N2 are the only known Influenza A virus subtypes currently circulating among humans. The virus does not cause ... H1N2 is a subtype of the species Influenza A virus (sometimes called bird flu virus). It is currently endemic in both human and ... Between December 1988 and March 1989, 19 influenza H1N2 virus isolates were identified in 6 cities in China, but the virus did ...
Influenza A viruses are significant for their potential for disease and death in humans and other animals. Influenza A virus ... H1N1, which caused the 1918 flu pandemic ("Spanish flu") and currently is causing seasonal human flu and the 2009 flu pandemic ... Influenza A virus subtype H5N1, also known as A(H5N1) or simply H5N1, is a subtype of the influenza A virus which can cause ... never previously susceptible to any influenza virus. H5N1 is a subtype of the species Influenza A virus of the Influenzavirus A ...
Swine influenza any strain of the influenza virus endemic in pigs (excludes H1N1 swine flu, which is a human virus) pigs close ... Barmah Forest virus kangaroos, wallabies, opossums mosquito bite Bird flu Influenza A virus subtype H5N1 wild birds, ... Field H, Young P, Yob JM, Mills J, Hall L, Mackenzie J (2001). "The natural history of Hendra and Nipah viruses". Microbes and ... Influenza Influenza A virus horses, pigs, domestic and wild birds, wild aquatic mammals such as seals and whales, minks and ...
Influenza viruses that are normally found in swine are known as swine influenza viruses (SIVs). The known SIV strains include ... Influenza A (H1N1) virus is the subtype of influenza A virus that was the most common cause of human influenza (flu) in 2009, ... North American swine influenza, North American avian influenza, human influenza, and swine influenza virus typically found in ... This colorized transmission electron micrograph shows H1N1 influenza virus particles. Surface proteins on the virus particles ...
... of swine influenza virus subtype H1N1 of A/Swine/Nebraska/(H1N1) were retrieved from protein sequence database situated at NCBI ... Diversity of Influenza Viruses in Swine and the Emergence of a Novel Human Pandemic Influenza A (H1N1). Influenza Other Respi ... The aim of this study was to analyse the mutation possibility of swine influenza virus sub-type A/Swine/Nebraska/(H1N1) from ... Amino acid sequences of NA and HA of swine influenza virus sub-type H1N1 strains were used for screening of 98-99% similar ...
From 1977, we have then the A-H1N1 flu virus being part of the pool or mixture of the seasonal flu viruses. ... The first is that the virus has mutated, therefore the vaccine is not good. Or second, it is another virus or other viruses, ... The article confirms as fact that this virus reappeared (the A-H1N1 virus) in 1977 because it had been resynthesized in a lab. ... From where did the 2009 swine-origin influenza A virus (H1N1) Emerge? ...
the evolution of swine influenza viruses in pigs, and in particular monitor hallmarks of adaptation to humans. The scope of ... storms" and haemorrhages seen in severe influenza infections.The influenza A virus subtypes H1N1, H1N2 and H3N2 are prevalent ... The influenza A virus subtypes H1N1, H1N2 and H3N2 ,HDFx A Novel _1_.pdf. ... File Entry: Krishnasarma pathy, (2017) The influenza A virus subtypes H1N1, H1N2 and H3N2 ,HDFx: A Novel Immunomodulator and ...
Swine influenza virus (SIV) is any strain of the influenza family of viruses that is endemic in pigs. As of 2009, the known SIV ... Influenza A (H1N1) virus is the subtype of influenza A virus that was the most common cause of human influenza (flu) in 2009. ... strains include influenza C and the subtypes of influenza A known as H1N1, H1N2, H3N1, H3N2, and H2N3.. Swine influenza virus ... For the H1N1/09 virus strain responsible for the 2009 flu pandemic, see Pandemic H1N1/09 virus. For the 2009 pandemic Influenza ...
H1N1) virus is the subtype of influenza A virus that was the most common cause of human influenza (flu) in 2009, and is ... is a subtype of viruses that causes influenza (flu).. New!!: Influenza A virus subtype H1N1 and Influenza A virus subtype H3N2 ... H1N1, H1N1 Flu, H1N1 Swine Flu, H1N1 diagnosis, H1N1 flu, H1N1 flu virus, H1N1 infection, H1N1 influenza, H1N1 virus, H1n1, ... Influenza, Influenza A virus, Influenza A virus subtype H1N2, Influenza A virus subtype H2N2, Influenza A virus subtype H2N3, ...
Both viruses were antigenically and genetically characterized. Continued surveillance of swine influenza A viruses is needed ... H1N1) virus that was also detected in the farmed pigs. ... in the Netherlands with a Eurasian avian-like swine influenza A ... Virus. Subtype. H1 clade. Virus neutralization titer for swine antiserum† swBe98. swG10. Ca09. swG99. swG12. swFl98. swG08. ... Human Infection with Eurasian Avian-Like Swine Influenza A(H1N1) Virus, the Netherlands, September 2019 Anna Parys, Elien ...
... as influenza B. Of the sub-typed influenza A viruses reported, 30.2% were influenza A(H1N1)pdm09 and 69.8% were influenza A( ... Influenza virus detection by type/subtype in countries, areas or territories:. *Influenza A(H1N1)pdm09: Australia, Bolivia ( ... Influenza A(H3N2) and B viruses were co-circulating in Asia at low levels, while A(H1N1)pdm09 virus detections were reported in ... Influenza A(H1N1) old seasonal virus: no report. *Influenza A(H3N2): Argentina, Australia, Bolivia (Plurinational State of), ...
... Taxonomy navigation. › H1N1 subtype ... Viruses. › Riboviria. › Negarnaviricota. › Polyploviricotina. › Insthoviricetes. › Articulavirales. › Orthomyxoviridae. › ... Taxonomy - Influenza A virus (A/Puerto Rico/8-CV10/1934(H1N1)) Basket 0 ...
Influenza matrix protein 2 (M2) is highly conserved across influenza A subtypes. To evaluate its efficacy as a vaccine ... This vaccination induced antibodies that cross-reacted with divergent M2 peptide from an H5N1 subtype. A DNA vaccine expressing ... This M2 prime-boost vaccination conferred broad protection against challenge with lethal influenza A, including an H5N1 strain ... Vaccination with M2, with key sequences represented, may provide broad protection against influenza A. ...
Influenza A Virus, H1N1 Subtype. Vaccine. Children. Adolescents. HIV-Infected. Perinatal HIV Infection. Treatment experienced. ... HAI Titers Against Seasonal Influenza Viruses Containing Trivalent Influenza Vaccine (TIV) [ Time Frame: Measured at entry, 21 ... HIV Infections H1N1 Influenza Virus Biological: Influenza A (H1N1) 2009 monovalent vaccine Phase 2 ... Experimental: Influenza A (H1N1) 2009 monovalent vaccine All participants received two doses of the H1N1 influenza virus ...
In Oceania, influenza type A viruses were more commonly isolated than influenza type B; both A(H3N2) and A(H1N1) subtypes ... The type(s)/subtype(s) of influenza virus that will circulate, the timing of onset and peaking, and the severity of the ... H1N1) viruses have been the most frequently isolated influenza viruses in the United States. Influenza A(H1N1) viruses were ... influenza A viruses were reported more frequently than influenza B viruses. In Africa, influenza A(H1N1) viruses were reported ...
Later studies showed that this novel H1N1 strain (henceforth, H1N1 or novel H1N1) is quite distinct from influenza viruses that ... H1N1 is a subtype of the type A influenza virus that causes an illness commonly known as the flu. There are three types of ... The influenza A virus subtypes H1N1, H1N2 and H3N2 are prevalent in pig populations worldwide. All scientific data point ... The Influenza a Virus Subtypes H1N1, H1N2 and H3N2 ,Hdfx: a Novel Immunomodulatorand Potential Fighter against Cytokine Storms ...
1982) Prevalence of hemagglutination inhibition antibody to current strains of the H3N2 and H1N1 subtypes of influenza A virus ... 1976) Swine influenza virus and the recycling of influenza-A viruses in man. Lancet 2(7979):244-247. ... we reconstruct the evolutionary origins of the 1918 pandemic H1N1 virus, the classic swine H1N1 influenza virus, and the ... Influenza Virus Reservoirs and Intermediate Hosts: Dogs, Horses, and New Possibilities for Influenza Virus Exposure of Humans ...
... trivalent inactivated influenza vaccine has been provided free-of-charge to older adults aged ≥60 years in Beijing, China, but ... no subtypes have been identified for Influenza B or Influenza C viruses. ... Influenza A Virus, H1n1 Subtype. A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 1 and ... It is also referred to as H1N1 influenza (because it is the H1N1 strain of virus). The H1N1 flu virus will be one of the main ...
During week 20, no influenza B viruses were reported, and both subtyped influenza A viruses were 2009 influenza A (H1N1. ... In addition, one seasonal influenza A (H1N1), 18 influenza A (H3N2), and 1,858 2009 influenza A (H1N1) virus isolates have been ... H1N1), 13 influenza A (H3N2), 23 influenza B, and 1,855 2009 influenza A (H1N1) virus isolates have been tested for resistance ... H1N1), 14 influenza A (H3N2), 32 influenza B, and 1,847 2009 influenza A (H1N1) viruses collected since September 1, 2009. ...
Information about Transmission of Avian Influenza A Viruses Between Animals and People - CDC ... Currently circulating Influenza A subtypes in humans are H3N2 and H1N1 viruses. Examples of different influenza A virus ... The segmented genome allows influenza A viruses from different species to mix and create a new virus if influenza A viruses ... For example, if a pig were infected with a human influenza A virus and an avian influenza A virus at the same time, the new ...
Existing Descriptor: INFLUENZA A VIRUS, H1N1 SUBTYPE. New entry term: Swine-Origin Influenza A H1N1 Virus ... the new influenza virus has been mostly isolated from infected humans, though many of its genes are derived from pig viruses. ... INFLUENZA A VIRUS, H1N1 SUBTYPE + HUMANS An article on "swine flu of the H1N1 subtype in swine" will be indexed as: INFLUENZA A ... "Swine Influenza Virus" from the descriptor INFLUENZA A VIRUS. This referred to the classical swine flu virus which has evolved ...
... and novel influenza virus discrimination. Influenza virus subtyping was based on matrix gene sequence variations reported ... The detection of pandemic influenza A/H1N1/09 and seasonal influenza viruses was performed by two methods. The first method ... Comparison of different assays for the detection of pandemic H1N1/09 virus.A previously characterized influenza A/H1N1/09 virus ... H1N1) 2009 strain, a set of human and animal influenza virus isolates was tested (Table S2). These influenza virus samples were ...
Influenza Virus Type A. Influenza Virus Type A (excluding 1918 influenza A (H1N1) strain and subtypes H5, H7 and H9). PATHOGEN ... seasonal influenza epidemics caused by influenza A/H3N2 viruses than during seasons in which other influenza A virus subtypes ... 1 influenza A (H3N2) virus, 1 influenza A (H1N1) virus and 1 influenza B virus(11,40). Each year, one or more virus strain ... NAME: Influenza virus type A (excluding 1918 influenza A (H1N1) strain and subtypes H5, H7 and H9). ...
A method for diagnosing hepatitis virus infection or a hepatitis disease condition in a subject based on hepatitis virus- ... human papilloma virus (HPV) and its many serotypes; influenza type A viruses, including subtypes H1N1 and H5N1; severe acute ... hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus (HEV ... hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and hepatitis E virus (HEV). 6. The method of claim 1 ...
We describe the distributions of antibody titers to subtypes 2009 H1N1 and H3N2. Using a model selection approach to fit ... For H1N1, our interpretation is that the two highest-titer subgroups correspond to recent and historical infection, which is ... serum samples from southern Vietnam collected between 2009 and 2013 from which we report antibody titers to the influenza virus ... mixture distributions, we show that 2009 H1N1 antibody titers fall into four titer subgroups and that H3N2 titers fall into ...
... but most faced a great deal of uncertainty during the 2009 influenza H1N1 epidemic. Questions remained about whether, when, and ... pandemic influenza plans and school closure statutes are intended to guide state and local officials, ... Influenza A Virus, H1N1 Subtype*. Influenza, Human / epidemiology, prevention & control*. Models, Organizational. Schools / ... a pandemic simulation based on Allegheny CountyInfluenza Other Respi VirusesYear: 201042617210.1111/j.1750-2659.2009.00122. ...
Influenza A Virus, H1n1 Subtype. A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 1 and ... European avian-like H1N1 (EA H1N1) SIVs are th.... Identification and genomic characterization of influenza viruses with ... efficacy of a high-growth reassortant H1N1 influenza virus vaccine against the European Avian-like H1N1 swine influenza virus ... Swine-Origin Influenza A H1N1 Virus. Intervention. Adjuvanted cell-derived, inactivated novel swine origin A/H1N1 monovalent ...
Influenza A Virus, H1N1 Subtype Infections ... $ 2000 November 2019 Diarrhea - Pipeline Review, H2 2019 $ 2000 November 2019 ... to 2028SummarySeasonal influenza is a contagious respiratory viral illness.There are four types of seasonal influenza viruses ( ... Seasonal Influenza: Epidemiology Forecast in Asia-Pacific Markets ...
  • The 2017/18 winter influenza season in Hong Kong SAR started in early January 2018, predominated by influenza B/Yamagata. (bioportfolio.com)
  • For the analytical specificity, 73 pig samples collected during 2017 and 2018 were analyzed, resulting in the identification of the subtype in 74.0% (62.9-82.7, CI 95%) of samples. (medworm.com)
  • Summary of the 2017-2018 influenza season. (healthline.com)
  • 2017. "Comparison of Influenza Epidemiological and Virological Characteristics between Outpatients and Inpatients in Zhejiang Province, China, March 2011-June 2015. (mdpi.com)
  • Sensitivity test results, expressed as the concentration of amantadine required to inhibit by 50% the growth of virus (ED 50 ) in tissue culture vary greatly (from 0.1μg/mL to 25.0 μg/mL) depending upon the assay protocol used, size of virus inoculum, isolates of influenza A virus strains tested, and the cell type used. (drugs.com)
  • Of the 205 antigenically characterized H1N1 viruses, 136 were from South or Central America, 42 from the United States, 18 from Asia, seven from Australia, New Zealand, and New Caledonia, and two from Africa. (cdc.gov)
  • Phylogenetic, seroarcheological, and epidemiological evidence indicates those born earlier or later than ∼1880-1900 would have had some protection against the 1918 H1N1 virus, whereas many young adults born from ∼1880-1900 may have lacked such protection because of childhood exposure to an antigenically distinct H3N8 virus. (pnas.org)
  • The phylogenetic results, combined with these other lines of evidence, suggest that the high mortality in 1918 among adults aged ∼20 to ∼40 y may have been due primarily to their childhood exposure to a doubly heterosubtypic putative H3N8 virus, which we estimate circulated from ∼1889-1900. (pnas.org)