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.
Simian Acquired Immunodeficiency Syndrome
Acquired defect of cellular immunity that occurs naturally in macaques infected with SRV serotypes, experimentally in monkeys inoculated with SRV or MASON-PFIZER MONKEY VIRUS; (MPMV), or in monkeys infected with SIMIAN IMMUNODEFICIENCY VIRUS.
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.
Macaca mulatta
A species of the genus MACACA inhabiting India, China, and other parts of Asia. The species is used extensively in biomedical research and adapts very well to living with humans.
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).
HIV-1
Virus Replication
Cytomegalovirus Infections
Infection with CYTOMEGALOVIRUS, characterized by enlarged cells bearing intranuclear inclusions. Infection may be in almost any organ, but the salivary glands are the most common site in children, as are the lungs in adults.
BK Virus
CD4 Lymphocyte Count
The number of CD4-POSITIVE T-LYMPHOCYTES per unit volume of BLOOD. Determination requires the use of a fluorescence-activated flow cytometer.
Antiretroviral Therapy, Highly Active
Drug regimens, for patients with HIV INFECTIONS, that aggressively suppress HIV replication. The regimens usually involve administration of three or more different drugs including a protease inhibitor.
Anti-HIV Agents
Agents used to treat AIDS and/or stop the spread of the HIV infection. These do not include drugs used to treat symptoms or opportunistic infections associated with AIDS.
CD4-Positive T-Lymphocytes
A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.
Viral Vaccines
Polyomavirus Infections
Infections with POLYOMAVIRUS, which are often cultured from the urine of kidney transplant patients. Excretion of BK VIRUS is associated with ureteral strictures and CYSTITIS, and that of JC VIRUS with progressive multifocal leukoencephalopathy (LEUKOENCEPHALOPATHY, PROGRESSIVE MULTIFOCAL).
SAIDS Vaccines
Vaccines or candidate vaccines designed to prevent SAIDS; (SIMIAN ACQUIRED IMMUNODEFICIENCY SYNDROME); and containing inactivated SIMIAN IMMUNODEFICIENCY VIRUS or type D retroviruses or some of their component antigens.
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.
Flaviviridae Infections
Infections with viruses of the family FLAVIVIRIDAE.
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.
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.
GB virus C
A species of virus (unassigned to a genus) in the family FLAVIVIRIDAE. It is genetically heterogeneous, of human origin, and transmitted by blood or blood products. Despite its alternate name (Hepatitis G virus), its pathogenicity remains controversial.
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.
Cytomegalovirus
A genus of the family HERPESVIRIDAE, subfamily BETAHERPESVIRINAE, infecting the salivary glands, liver, spleen, lungs, eyes, and other organs, in which they produce characteristically enlarged cells with intranuclear inclusions. Infection with Cytomegalovirus is also seen as an opportunistic infection in AIDS.
CD8-Positive T-Lymphocytes
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.
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).
DNA Virus Infections
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).
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.
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)
Antibodies, Neutralizing
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)
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.
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.
Organophosphonates
Hepatitis, Viral, Human
INFLAMMATION of the LIVER in humans due to infection by VIRUSES. There are several significant types of human viral hepatitis with infection caused by enteric-transmission (HEPATITIS A; HEPATITIS E) or blood transfusion (HEPATITIS B; HEPATITIS C; and HEPATITIS D).
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.
HIV Antibodies
Antibodies reactive with HIV ANTIGENS.
Porcine respiratory and reproductive syndrome virus
Macaca nemestrina
Vaccines, Attenuated
Hepatitis C Antibodies
Antibodies to the HEPATITIS C ANTIGENS including antibodies to envelope, core, and non-structural proteins.
Gene Products, env
Macaca
Yellow fever virus
Torque teno virus
Acquired Immunodeficiency Syndrome
An acquired defect of cellular immunity associated with infection by the human immunodeficiency virus (HIV), a CD4-positive T-lymphocyte count under 200 cells/microliter or less than 14% of total lymphocytes, and increased susceptibility to opportunistic infections and malignant neoplasms. Clinical manifestations also include emaciation (wasting) and dementia. These elements reflect criteria for AIDS as defined by the CDC in 1993.
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.
Disease Models, Animal
Alphavirus Infections
West Nile Virus Vaccines
Vaccines or candidate vaccines used to prevent infection with WEST NILE VIRUS.
Plasma
HIV Long-Term Survivors
Persons who have experienced prolonged survival of HIV infection. This includes the full spectrum of untreated, HIV-infected long-term asymptomatics to those with AIDS who have survived due to successful treatment.
Circovirus
A genus of the family CIRCOVIRIDAE that infects SWINE; PSITTACINES; and non-psittacine BIRDS. Species include Beak and feather disease virus causing a fatal disease in psittacine birds, and Porcine circovirus causing postweaning multisystemic wasting syndrome in pigs (PORCINE POSTWEANING MULTISYSTEMIC WASTING SYNDROME).
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.
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.
Hepatitis Antibodies
Flaviviridae
A family of RNA viruses, many of which cause disease in humans and domestic animals. There are three genera FLAVIVIRUS; PESTIVIRUS; and HEPACIVIRUS, as well as several unassigned species.
Dengue Vaccines
Vaccines or candidate vaccines used to prevent infection with DENGUE VIRUS. These include live-attenuated, subunit, DNA, and inactivated vaccines.
Yellow Fever Vaccine
Vaccine used to prevent YELLOW FEVER. It consists of a live attenuated 17D strain of the YELLOW FEVER VIRUS.