Dengue Virus
A species of the genus FLAVIVIRUS which causes an acute febrile and sometimes hemorrhagic disease in man. Dengue is mosquito-borne and four serotypes are known.
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).
Dengue
An acute febrile disease transmitted by the bite of AEDES mosquitoes infected with DENGUE VIRUS. It is self-limiting and characterized by fever, myalgia, headache, and rash. SEVERE DENGUE is a more virulent form of dengue.
Orthobunyavirus
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.
Pseudorabies
Severe Dengue
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.
Seroepidemiologic Studies
EPIDEMIOLOGIC STUDIES based on the detection through serological testing of characteristic change in the serum level of specific ANTIBODIES. Latent subclinical infections and carrier states can thus be detected in addition to clinically overt cases.
Swine Diseases
Diseases of domestic swine and of the wild boar of the genus Sus.
Antibodies, Neutralizing
Dengue Vaccines
Vaccines or candidate vaccines used to prevent infection with DENGUE VIRUS. These include live-attenuated, subunit, DNA, and inactivated vaccines.
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).
Aedes
A genus of mosquitoes (CULICIDAE) frequently found in tropical and subtropical regions. YELLOW FEVER and DENGUE are two of the diseases that can be transmitted by species of this genus.
Cattle
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.
Hemagglutination Inhibition Tests
Cross Reactions
Epitopes
Sites on an antigen that interact with specific antibodies.
Viral Envelope Proteins
Layers of protein which surround the capsid in animal viruses with tubular nucleocapsids. The envelope consists of an inner layer of lipids and virus specified proteins also called membrane or matrix proteins. The outer layer consists of one or more types of morphological subunits called peplomers which project from the viral envelope; this layer always consists of glycoproteins.
Virus Replication
Viral Vaccines
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.
Serotyping
Immune Sera
Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.
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.
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.
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.
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.
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.
Horse Diseases
Diseases of domestic and wild horses of the species Equus caballus.
Flavivirus
A genus of FLAVIVIRIDAE containing several subgroups and many species. Most are arboviruses transmitted by mosquitoes or ticks. The type species is YELLOW FEVER VIRUS.
Immunoglobulin G
Transmissible gastroenteritis virus
A species of CORONAVIRUS causing a fatal disease to pigs under 3 weeks old.
Yellow fever virus
The type species of the FLAVIVIRUS genus. Principal vector transmission to humans is by AEDES spp. mosquitoes.
HIV Antibodies
Antibodies reactive with HIV ANTIGENS.
Antibody-Dependent Enhancement
Enhancement of viral infectivity caused by non-neutralizing antibodies. There are at least two mechanisms known to account for this: mediation by Fc receptors (RECEPTORS, FC) or by complement receptors (RECEPTORS, COMPLEMENT). Either the virus is complexed with antiviral IMMUNOGLOBULIN G and binds to Fc receptors, or virus is coated with antiviral IMMUNOGLOBULIN M and binds to complement receptors.
Antibody Specificity
The property of antibodies which enables them to react with some ANTIGENIC DETERMINANTS and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site.
Arboviruses
Arthropod-borne viruses. A non-taxonomic designation for viruses that can replicate in both vertebrate hosts and arthropod vectors. Included are some members of the following families: ARENAVIRIDAE; BUNYAVIRIDAE; REOVIRIDAE; TOGAVIRIDAE; and FLAVIVIRIDAE. (From Dictionary of Microbiology and Molecular Biology, 2nd ed)
Coronaviridae
Spherical RNA viruses, in the order NIDOVIRALES, infecting a wide range of animals including humans. Transmission is by fecal-oral and respiratory routes. Mechanical transmission is also common. There are two genera: CORONAVIRUS and TOROVIRUS.
Immunoglobulin M
Receptors, Virus
Viral Nonstructural Proteins
Proteins encoded by a VIRAL GENOME that are produced in the organisms they infect, but not packaged into the VIRUS PARTICLES. Some of these proteins may play roles within the infected cell during VIRUS REPLICATION or act in regulation of virus replication or VIRUS ASSEMBLY.
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.
Insect Vectors
Encephalitis Virus, St. Louis
A species of FLAVIVIRUS, one of the Japanese encephalitis virus group (ENCEPHALITIS VIRUSES, JAPANESE), which is the etiologic agent of ST. LOUIS ENCEPHALITIS in the United States, the Caribbean, and Central and South America.
Culicidae
Herpesvirus 1, Suid
A species of VARICELLOVIRUS producing a respiratory infection (PSEUDORABIES) in swine, its natural host. It also produces an usually fatal ENCEPHALOMYELITIS in cattle, sheep, dogs, cats, foxes, and mink.
Capsid Proteins
Proteins that form the CAPSID of VIRUSES.
Sensitivity and Specificity
Disease Outbreaks
Horses
Large, hoofed mammals of the family EQUIDAE. Horses are active day and night with most of the day spent seeking and consuming food. Feeding peaks occur in the early morning and late afternoon, and there are several daily periods of rest.
Amino Acid Sequence
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.
Vaccines, Attenuated
West Nile Fever
A mosquito-borne viral illness caused by the WEST NILE VIRUS, a FLAVIVIRUS and endemic to regions of Africa, Asia, and Europe. Common clinical features include HEADACHE; FEVER; maculopapular rash; gastrointestinal symptoms; and lymphadenopathy. MENINGITIS; ENCEPHALITIS; and MYELITIS may also occur. The disease may occasionally be fatal or leave survivors with residual neurologic deficits. (From Joynt, Clinical Neurology, 1996, Ch26, p13; Lancet 1998 Sep 5;352(9130):767-71)
Complement Fixation Tests
Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.
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.
HIV Envelope Protein gp120
External envelope protein of the human immunodeficiency virus which is encoded by the HIV env gene. It has a molecular weight of 120 kDa and contains numerous glycosylation sites. Gp120 binds to cells expressing CD4 cell-surface antigens, most notably T4-lymphocytes and monocytes/macrophages. Gp120 has been shown to interfere with the normal function of CD4 and is at least partly responsible for the cytopathic effect of HIV.
Radioimmunoprecipitation Assay
Sensitive assay using radiolabeled ANTIGENS to detect specific ANTIBODIES in SERUM. The antigens are allowed to react with the serum and then precipitated using a special reagent such as PROTEIN A sepharose beads. The bound radiolabeled immunoprecipitate is then commonly analyzed by gel electrophoresis.
Gastroenteritis, Transmissible, of Swine
A condition of chronic gastroenteritis in adult pigs and fatal gastroenteritis in piglets caused by a CORONAVIRUS.
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.
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.
Epitope Mapping
Methods used for studying the interactions of antibodies with specific regions of protein antigens. Important applications of epitope mapping are found within the area of immunochemistry.
Haplorhini
Vaccines, Inactivated
Virus Assembly
The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.
Cricetinae
Hemagglutination Tests
Sensitive tests to measure certain antigens, antibodies, or viruses, using their ability to agglutinate certain erythrocytes. (From Stedman, 26th ed)
Vaccination
Encephalitis Virus, Japanese
A species of FLAVIVIRUS, one of the Japanese encephalitis virus group (ENCEPHALITIS VIRUSES, JAPANESE), which is the etiological agent of Japanese encephalitis found in Asia, southeast Asia, and the Indian subcontinent.
Flavivirus Infections
Infections with viruses of the genus FLAVIVIRUS, family FLAVIVIRIDAE.
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).
Respiratory Syncytial Viruses
Bunyaviridae Infections
Virus diseases caused by the BUNYAVIRIDAE.
HIV-1
Rotavirus
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.
Herpesvirus 1, Bovine
A species of VARICELLOVIRUS that causes INFECTIOUS BOVINE RHINOTRACHEITIS and other associated syndromes in CATTLE.
Enterovirus
Cattle Diseases
Diseases of domestic cattle of the genus Bos. It includes diseases of cows, yaks, and zebus.
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.
Encephalitis Virus, California
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.
Encephalitis, St. Louis
A viral encephalitis caused by the St. Louis encephalitis virus (ENCEPHALITIS VIRUS, ST. LOUIS), a FLAVIVIRUS. It is transmitted to humans and other vertebrates primarily by mosquitoes of the genus CULEX. The primary animal vectors are wild birds and the disorder is endemic to the midwestern and southeastern United States. Infections may be limited to an influenza-like illness or present as an ASEPTIC MENINGITIS or ENCEPHALITIS. Clinical manifestations of the encephalitic presentation may include SEIZURES, lethargy, MYOCLONUS, focal neurologic signs, COMA, and DEATH. (From Adams et al., Principles of Neurology, 6th ed, p750)
Encephalitis, Japanese
A mosquito-borne encephalitis caused by the Japanese B encephalitis virus (ENCEPHALITIS VIRUS, JAPANESE) occurring throughout Eastern Asia and Australia. The majority of infections occur in children and are subclinical or have features limited to transient fever and gastrointestinal symptoms. Inflammation of the brain, spinal cord, and meninges may occur and lead to transient or permanent neurologic deficits (including a POLIOMYELITIS-like presentation); SEIZURES; COMA; and death. (From Adams et al., Principles of Neurology, 6th ed, p751; Lancet 1998 Apr 11;351(9109):1094-7)
Bunyaviridae
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.
Bovine Virus Diarrhea-Mucosal Disease
Acute disease of cattle caused by the bovine viral diarrhea viruses (DIARRHEA VIRUSES, BOVINE VIRAL). Often mouth ulcerations are the only sign but fever, diarrhea, drop in milk yield, and loss of appetite are also seen. Severity of clinical disease varies and is strain dependent. Outbreaks are characterized by low morbidity and high mortality.
Epitopes, B-Lymphocyte
Antigenic determinants recognized and bound by the B-cell receptor. Epitopes recognized by the B-cell receptor are located on the surface of the antigen.
Simbu virus
A species in the ORTHOBUNYAVIRUS genus of the family BUNYAVIRIDAE family. Previously a large group of serotypes, most are now considered separate species.
Simian virus 40
Yellow Fever
An acute infectious disease primarily of the tropics, caused by a virus and transmitted to man by mosquitoes of the genera Aedes and Haemagogus. The severe form is characterized by fever, HEMOLYTIC JAUNDICE, and renal damage.
Infectious Bovine Rhinotracheitis
A herpesvirus infection of CATTLE characterized by INFLAMMATION and NECROSIS of the mucous membranes of the upper RESPIRATORY TRACT.
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.
Mumps virus
Rabies Vaccines
Vaccines or candidate vaccines used to prevent and treat RABIES. The inactivated virus vaccine is used for preexposure immunization to persons at high risk of exposure, and in conjunction with rabies immunoglobulin, for postexposure prophylaxis.
Thailand
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).
Cells, Cultured
Measles virus
Bluetongue virus
Goats
Hantavirus
A genus of the family BUNYAVIRIDAE causing HANTAVIRUS INFECTIONS, first identified during the Korean war. Infection is found primarily in rodents and humans. Transmission does not appear to involve arthropods. HANTAAN VIRUS is the type species.
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.
Reverse Transcriptase Polymerase Chain Reaction
Nicaragua
I'm sorry for any confusion, but "Nicaragua" is not a medical term and does not have a medical definition. Nicaragua is the largest country in the Central American isthmus, bordering Honduras to the north and Costa Rica to the south. It has both Atlantic and Pacific coasts. The term you might be looking for is "Nicotine," which is a highly addictive stimulant found in tobacco leaves and is used as an ingredient in various products, including cigarettes, smokeless tobacco, and some medications.
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.
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.
Antibody Affinity
A measure of the binding strength between antibody and a simple hapten or antigen determinant. It depends on the closeness of stereochemical fit between antibody combining sites and antigen determinants, on the size of the area of contact between them, and on the distribution of charged and hydrophobic groups. It includes the concept of "avidity," which refers to the strength of the antigen-antibody bond after formation of reversible complexes.
Evaluation Studies as Topic
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.
Influenza A Virus, H1N1 Subtype
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.
Rabbits
Lyssavirus
A genus of the family RHABDOVIRIDAE that includes RABIES VIRUS and other rabies-like viruses.
Antigen-Antibody Reactions
The processes triggered by interactions of ANTIBODIES with their ANTIGENS.
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.
Immunization
Deliberate stimulation of the host's immune response. ACTIVE IMMUNIZATION involves administration of ANTIGENS or IMMUNOLOGIC ADJUVANTS. PASSIVE IMMUNIZATION involves administration of IMMUNE SERA or LYMPHOCYTES or their extracts (e.g., transfer factor, immune RNA) or transplantation of immunocompetent cell producing tissue (thymus or bone marrow).
Arteritis Virus, Equine
Mice, Inbred BALB C
Japanese Encephalitis Vaccines
Vaccines or candidate vaccines used to prevent infection with Japanese B encephalitis virus (ENCEPHALITIS VIRUS, JAPANESE).
Antibody Formation
The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.
Encephalitis, Arbovirus
Infections of the brain caused by arthropod-borne viruses (i.e., arboviruses) primarily from the families TOGAVIRIDAE; FLAVIVIRIDAE; BUNYAVIRIDAE; REOVIRIDAE; and RHABDOVIRIDAE. Life cycles of these viruses are characterized by ZOONOSES, with birds and lower mammals serving as intermediate hosts. The virus is transmitted to humans by the bite of mosquitoes (CULICIDAE) or TICKS. Clinical manifestations include fever, headache, alterations of mentation, focal neurologic deficits, and COMA. (From Clin Microbiol Rev 1994 Jan;7(1):89-116; Walton, Brain's Diseases of the Nervous System, 10th ed, p321)
HIV Envelope Protein gp41
Transmembrane envelope protein of the HUMAN IMMUNODEFICIENCY VIRUS which is encoded by the HIV env gene. It has a molecular weight of 41,000 and is glycosylated. The N-terminal part of gp41 is thought to be involved in CELL FUSION with the CD4 ANTIGENS of T4 LYMPHOCYTES, leading to syncytial formation. Gp41 is one of the most common HIV antigens detected by IMMUNOBLOTTING.
Reoviridae
A family of unenveloped RNA viruses with cubic symmetry. The twelve genera include ORTHOREOVIRUS; ORBIVIRUS; COLTIVIRUS; ROTAVIRUS; Aquareovirus, Cypovirus, Phytoreovirus, Fijivirus, Seadornavirus, Idnoreovirus, Mycoreovirus, and Oryzavirus.
Vaccines, Synthetic
Plantibodies
Recombinant antibodies produced in TRANSGENIC PLANTS. The plants serve as BIOREACTORS to produce the antibodies for medical use or industrial processes.
Respiratory Syncytial Virus, Bovine
A species of PNEUMOVIRUS causing an important respiratory infection in cattle. Symptoms include fever, conjunctivitis, and respiratory distress.
Culture Techniques
Methods of maintaining or growing biological materials in controlled laboratory conditions. These include the cultures of CELLS; TISSUES; organs; or embryo in vitro. Both animal and plant tissues may be cultured by a variety of methods. Cultures may derive from normal or abnormal tissues, and consist of a single cell type or mixed cell types.
Influenza A Virus, H3N2 Subtype
Gene Products, env
Retroviral proteins, often glycosylated, coded by the envelope (env) gene. They are usually synthesized as protein precursors (POLYPROTEINS) and later cleaved into the final viral envelope glycoproteins by a viral protease.
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.
Virology
The study of the structure, growth, function, genetics, and reproduction of viruses, and VIRUS DISEASES.
Leukemia Virus, Feline
Hantaan virus
The type species of the genus HANTAVIRUS infecting the rodent Apodemus agrarius and humans who come in contact with it. It causes syndromes of hemorrhagic fever associated with vascular and especially renal pathology.
Hemorrhagic Fever with Renal Syndrome
An acute febrile disease occurring predominately in Asia. It is characterized by fever, prostration, vomiting, hemorrhagic phenonema, shock, and renal failure. It is caused by any one of several closely related species of the genus Hantavirus. The most severe form is caused by HANTAAN VIRUS whose natural host is the rodent Apodemus agrarius. Milder forms are caused by SEOUL VIRUS and transmitted by the rodents Rattus rattus and R. norvegicus, and the PUUMALA VIRUS with transmission by Clethrionomys galreolus.
Sequence Analysis, DNA
Conjunctivitis, Viral
Host-Pathogen Interactions
Yellow Fever Vaccine
Vaccine used to prevent YELLOW FEVER. It consists of a live attenuated 17D strain of the YELLOW FEVER VIRUS.
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.
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.
Foot-and-Mouth Disease
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.
DNA Primers
Chickens
Immunization, Passive
Transfer of immunity from immunized to non-immune host by administration of serum antibodies, or transplantation of lymphocytes (ADOPTIVE TRANSFER).
Glycoproteins
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
Encephalomyelitis, Equine
A group of ALPHAVIRUS INFECTIONS which affect horses and man, transmitted via the bites of mosquitoes. Disorders in this category are endemic to regions of South America and North America. In humans, clinical manifestations vary with the type of infection, and range from a mild influenza-like syndrome to a fulminant encephalitis. (From Joynt, Clinical Neurology, 1996, Ch26, pp8-10)
Diphtheria Antitoxin
Simplexvirus
Base Sequence
Bird Diseases
Virus Attachment
Adenovirus Infections, Human
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.
Infectious bronchitis virus
A species of CORONAVIRUS causing infections in chickens and possibly pheasants. Chicks up to four weeks old are the most severely affected.
Antigen-Antibody Complex
Antigenic Variation
Change in the surface ANTIGEN of a microorganism. There are two different types. One is a phenomenon, especially associated with INFLUENZA VIRUSES, where they undergo spontaneous variation both as slow antigenic drift and sudden emergence of new strains (antigenic shift). The second type is when certain PARASITES, especially trypanosomes, PLASMODIUM, and BORRELIA, survive the immune response of the host by changing the surface coat (antigen switching). (From Herbert et al., The Dictionary of Immunology, 4th ed)
Rabies
Acute VIRAL CNS INFECTION affecting mammals, including humans. It is caused by RABIES VIRUS and usually spread by contamination with virus-laden saliva of bites inflicted by rabid animals. Important animal vectors include the dog, cat, bat, fox, raccoon, skunk, and wolf.
Models, Molecular
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.
Vietnam
Coronavirus
A genus of the family CORONAVIRIDAE which causes respiratory or gastrointestinal disease in a variety of vertebrates.
Dogs
Enterovirus Infections
Enterovirus Infections are acute viral illnesses caused by various Enterovirus serotypes, primarily transmitted through the fecal-oral route, manifesting as a wide range of clinical symptoms, from asymptomatic or mild self-limiting fever to severe and potentially life-threatening conditions, such as meningitis, encephalitis, myocarditis, and neonatal sepsis-like illness, depending on the age, immune status, and serotype of the infected individual.
AIDS Vaccines
Vaccines or candidate vaccines containing inactivated HIV or some of its component antigens and designed to prevent or treat AIDS. Some vaccines containing antigens are recombinantly produced.
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.
Virus Internalization
The entering of cells by viruses following VIRUS ATTACHMENT. This is achieved by ENDOCYTOSIS, by direct MEMBRANE FUSION of the viral membrane with the CELL MEMBRANE, or by translocation of the whole virus across the cell membrane.
Enterovirus B, Human
A species of ENTEROVIRUS infecting humans and containing 36 serotypes. It is comprised of all the echoviruses and a few coxsackieviruses, including all of those previously named coxsackievirus B.
Porcine Reproductive and Respiratory Syndrome
A syndrome characterized by outbreaks of late term abortions, high numbers of stillbirths and mummified or weak newborn piglets, and respiratory disease in young unweaned and weaned pigs. It is caused by PORCINE RESPIRATORY AND REPRODUCTIVE SYNDROME VIRUS. (Radostits et al., Veterinary Medicine, 8th ed, p1048)
Guinea Pigs
Antibodies
Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).
Encephalitis Virus, Eastern Equine
A species of ALPHAVIRUS causing encephalomyelitis in Equidae and humans. The virus ranges along the Atlantic seaboard of the United States and Canada and as far south as the Caribbean, Mexico, and parts of Central and South America. Infections in horses show a mortality of up to 90 percent and in humans as high as 80 percent in epidemics.