Studies of the number of cases where human immunodeficiency virus (HIV) is present in a specific population at a designated time. The presence in a given individual is determined by the finding of HIV antibodies in the serum (HIV SEROPOSITIVITY).
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.
HIV Protease Inhibitors
Inhibitors of HIV PROTEASE, an enzyme required for production of proteins needed for viral assembly.
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.
HIV Core Protein p24
A major core protein of the human immunodeficiency virus encoded by the HIV gag gene. HIV-seropositive individuals mount a significant immune response to p24 and thus detection of antibodies to p24 is one basis for determining HIV infection by ELISA and Western blot assays. The protein is also being investigated as a potential HIV immunogen in vaccines.
HIV Reverse Transcriptase
A reverse transcriptase encoded by the POL GENE of HIV. It is a heterodimer of 66 kDa and 51 kDa subunits that are derived from a common precursor protein. The heterodimer also includes an RNAse H activity (RIBONUCLEASE H, HUMAN IMMUNODEFICIENCY VIRUS) that plays an essential role the viral replication process.
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.
Cellular receptors that bind the human immunodeficiency virus that causes AIDS. Included are CD4 ANTIGENS, found on T4 lymphocytes, and monocytes/macrophages, which bind to the HIV ENVELOPE PROTEIN GP120.
Enzyme of the human immunodeficiency virus that is required for post-translational cleavage of gag and gag-pol precursor polyproteins into functional products needed for viral assembly. HIV protease is an aspartic protease encoded by the amino terminus of the pol gene.
The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.
HIV Long-Term Survivors
Sexual behaviors which are high-risk for contracting SEXUALLY TRANSMITTED DISEASES or for producing PREGNANCY.
AIDS-Related Opportunistic Infections
Opportunistic infections found in patients who test positive for human immunodeficiency virus (HIV). The most common include PNEUMOCYSTIS PNEUMONIA, Kaposi's sarcoma, cryptosporidiosis, herpes simplex, toxoplasmosis, cryptococcosis, and infections with Mycobacterium avium complex, Microsporidium, and Cytomegalovirus.
Health Knowledge, Attitudes, Practice
Simultaneous infection of a host organism by two or more pathogens. In virology, coinfection commonly refers to simultaneous infection of a single cell by two or more different viruses.
A syndrome characterized by chronic, well-established DIARRHEA (greater than one month in duration) without an identified infectious cause after thorough evaluation, in an HIV-positive individual. It is thought to be due to direct or indirect effects of HIV on the enteric mucosa. HIV enteropathy is a diagnosis of exclusion and can be made only after other forms of diarrheal illness have been ruled out. (Harrison's Principles of Internal Medicine, 13th ed, pp1607-8; Haubrich et al., Bockus Gastroenterology, 5th ed, p1155)
Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.
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.
Sexual behavior that prevents or reduces the spread of SEXUALLY TRANSMITTED DISEASES or PREGNANCY.
AIDS Dementia Complex
A neurologic condition associated with the ACQUIRED IMMUNODEFICIENCY SYNDROME and characterized by impaired concentration and memory, slowness of hand movements, ATAXIA, incontinence, apathy, and gait difficulties associated with HIV-1 viral infection of the central nervous system. Pathologic examination of the brain reveals white matter rarefaction, perivascular infiltrates of lymphocytes, foamy macrophages, and multinucleated giant cells. (From Adams et al., Principles of Neurology, 6th ed, pp760-1; N Engl J Med, 1995 Apr 6;332(14):934-40)
Sudden outbreaks of a disease in a country or region not previously recognized in that area, or a rapid increase in the number of new cases of a previous existing endemic disease. Epidemics can also refer to outbreaks of disease in animal or plant populations.
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.
HIV Fusion Inhibitors
Inhibitors of the fusion of HIV to host cells, preventing viral entry. This includes compounds that block attachment of HIV ENVELOPE PROTEIN GP120 to CD4 RECEPTORS.
HIV Wasting Syndrome
Involuntary weight loss of greater than 10 percent associated with intermittent or constant fever and chronic diarrhea or fatigue for more than 30 days in the absence of a defined cause other than HIV infection. A constant feature is major muscle wasting with scattered myofiber degeneration. A variety of etiologies, which vary among patients, contributes to this syndrome. (From Harrison's Principles of Internal Medicine, 13th ed, p1611).
HIV Integrase Inhibitors
Inhibitors of HIV INTEGRASE, an enzyme required for integration of viral DNA into cellular DNA.
People who engage in occupational sexual behavior in exchange for economic rewards or other extrinsic considerations.
An HIV species related to HIV-1 but carrying different antigenic components and with differing nucleic acid composition. It shares serologic reactivity and sequence homology with the simian Lentivirus SIMIAN IMMUNODEFICIENCY VIRUS and infects only T4-lymphocytes expressing the CD4 phenotypic marker.
Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.
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.
The practice of making choices about SEXUAL PARTNERS based on their HIV status.
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.
Interviews as Topic
Risk Reduction Behavior
The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases, new or old, in the population at a given time.
Enzyme of the HUMAN IMMUNODEFICIENCY VIRUS that is required to integrate viral DNA into cellular DNA in the nucleus of a host cell. HIV integrase is a DNA nucleotidyltransferase encoded by the pol gene.
A dideoxynucleoside compound in which the 3'-hydroxy group on the sugar moiety has been replaced by an azido group. This modification prevents the formation of phosphodiester linkages which are needed for the completion of nucleic acid chains. The compound is a potent inhibitor of HIV replication, acting as a chain-terminator of viral DNA during reverse transcription. It improves immunologic function, partially reverses the HIV-induced neurological dysfunction, and improves certain other clinical abnormalities associated with AIDS. Its principal toxic effect is dose-dependent suppression of bone marrow, resulting in anemia and leukopenia.
Truthful revelation of information, specifically when the information disclosed is likely to be psychologically painful ("bad news") to the recipient (e.g., revelation to a patient or a patient's family of the patient's DIAGNOSIS or PROGNOSIS) or embarrassing to the teller (e.g., revelation of medical errors).
CCR receptors with specificity for CHEMOKINE CCL3; CHEMOKINE CCL4; and CHEMOKINE CCL5. They are expressed at high levels in T-LYMPHOCYTES; B-LYMPHOCYTES; MACROPHAGES; MAST CELLS; and NK CELLS. The CCR5 receptor is used by the HUMAN IMMUNODEFICIENCY VIRUS to infect cells.
Penal institutions, or places of confinement for war prisoners.
Centers for Disease Control and Prevention (U.S.)
An agency of the UNITED STATES PUBLIC HEALTH SERVICE that conducts and supports programs for the prevention and control of disease and provides consultation and assistance to health departments and other countries.
Usage of a single needle among two or more people for injecting drugs. Needle sharing is a high-risk behavior for contracting infectious disease.
55-kDa antigens found on HELPER-INDUCER T-LYMPHOCYTES and on a variety of other immune cell types. CD4 antigens are members of the immunoglobulin supergene family and are implicated as associative recognition elements in MAJOR HISTOCOMPATIBILITY COMPLEX class II-restricted immune responses. On T-lymphocytes they define the helper/inducer subset. CD4 antigens also serve as INTERLEUKIN-15 receptors and bind to the HIV receptors, binding directly to the HIV ENVELOPE PROTEIN GP120.
Reverse Transcriptase Inhibitors
A republic in southern Africa, south of ANGOLA and west of BOTSWANA. Its capital is Windhoek.
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)
Statistical models which describe the relationship between a qualitative dependent variable (that is, one which can take only certain discrete values, such as the presence or absence of a disease) and an independent variable. A common application is in epidemiology for estimating an individual's risk (probability of a disease) as a function of a given risk factor.
Testing or screening required by federal, state, or local law or other agencies for the diagnosis of specified conditions. It is usually limited to specific populations such as categories of health care providers, members of the military, and prisoners or to specific situations such as premarital examinations or donor screening.
Ambulatory Care Facilities
tat Gene Products, Human Immunodeficiency Virus
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
Health Services Accessibility
Sexually Transmitted Diseases, Viral
A kingdom in southern Africa, west of MOZAMBIQUE. Its capital is Mbabane. The area was settled by the Swazi branch of the Zulu nation in the early 1880's, with its independence guaranteed by the British and Transvaal governments in 1881 and 1884. With limited self-government introduced in 1962, it became independent in 1968. Swazi is the Zulu name for the people who call themselves Swati, from Mswati, the name of a 16th century king, from a word meaning stick or rod. (From Webster's New Geographical Dictionary, 1988, p1170 & Room, Brewer's Dictionary of Names, 1992, p527)
Drugs used in the treatment of tuberculosis. They are divided into two main classes: "first-line" agents, those with the greatest efficacy and acceptable degrees of toxicity used successfully in the great majority of cases; and "second-line" drugs used in drug-resistant cases or those in which some other patient-related condition has compromised the effectiveness of primary therapy.
gag Gene Products, Human 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.
Communicable Disease Control
A potent, non-nucleoside reverse transcriptase inhibitor used in combination with nucleoside analogues for treatment of HIV INFECTIONS and AIDS.
Care provided the pregnant woman in order to prevent complications, and decrease the incidence of maternal and prenatal mortality.
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
A set of techniques used when variation in several variables has to be studied simultaneously. In statistics, multivariate analysis is interpreted as any analytic method that allows simultaneous study of two or more dependent variables.
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.
An HIV protease inhibitor that works by interfering with the reproductive cycle of HIV. It also inhibits CYTOCHROME P-450 CYP3A.
A republic in western Africa, south of MALI and BURKINA FASO, bordered by GHANA on the east. Its administrative capital is Abidjan and Yamoussoukro has been the official capital since 1983. The country was formerly called Ivory Coast.
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.
Support systems that provide assistance and encouragement to individuals with physical or emotional disabilities in order that they may better cope. Informal social support is usually provided by friends, relatives, or peers, while formal assistance is provided by churches, groups, etc.
A prodromal phase of infection with the human immunodeficiency virus (HIV). Laboratory criteria separating AIDS-related complex (ARC) from AIDS include elevated or hyperactive B-cell humoral immune responses, compared to depressed or normal antibody reactivity in AIDS; follicular or mixed hyperplasia in ARC lymph nodes, leading to lymphocyte degeneration and depletion more typical of AIDS; evolving succession of histopathological lesions such as localization of Kaposi's sarcoma, signaling the transition to the full-blown AIDS.
Identification of those persons (or animals) who have had such an association with an infected person, animal, or contaminated environment as to have had the opportunity to acquire the infection. Contact tracing is a generally accepted method for the control of sexually transmitted diseases.
A method of data collection and a QUALITATIVE RESEARCH tool in which a small group of individuals are brought together and allowed to interact in a discussion of their opinions about topics, issues, or questions.
Gene Products, tat
Trans-acting transcription factors produced by retroviruses such as HIV. They are nuclear proteins whose expression is required for viral replication. The tat protein stimulates LONG TERMINAL REPEAT-driven RNA synthesis for both viral regulatory and viral structural proteins. tat stands for trans-activation of transcription.
A purine base and a fundamental unit of ADENINE NUCLEOTIDES.
HIV-Associated Lipodystrophy Syndrome
pol Gene Products, Human Immunodeficiency Virus
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.
Persons living in the United States of Mexican (MEXICAN AMERICANS), Puerto Rican, Cuban, Central or South American, or other Spanish culture or origin. The concept does not include Brazilian Americans or Portuguese Americans.
INFLAMMATION of the LIVER in humans caused by a member of the ORTHOHEPADNAVIRUS genus, HEPATITIS B VIRUS. It is primarily transmitted by parenteral exposure, such as transfusion of contaminated blood or blood products, but can also be transmitted via sexual or intimate personal contact.
Infectious organisms in the BLOOD, of which the predominant medical interest is their contamination of blood-soiled linens, towels, gowns, BANDAGES, other items from individuals in risk categories, NEEDLES and other sharp objects, MEDICAL WASTE and DENTAL WASTE, all of which health workers are exposed to. This concept is differentiated from the clinical conditions of BACTEREMIA; VIREMIA; and FUNGEMIA where the organism is present in the blood of a patient as the result of a natural infectious process.
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.
nef Gene Products, Human Immunodeficiency Virus
The sexual functions, activities, attitudes, and orientations of an individual. Sexuality, male or female, becomes evident at PUBERTY under the influence of gonadal steroids (TESTOSTERONE or ESTRADIOL), and social effects.
A potent and specific HIV protease inhibitor that appears to have good oral bioavailability.
The religion stemming from the life, teachings, and death of Jesus Christ: the religion that believes in God as the Father Almighty who works redemptively through the Holy Spirit for men's salvation and that affirms Jesus Christ as Lord and Savior who proclaimed to man the gospel of salvation. (From Webster, 3d ed)
A soft, loose-fitting polyurethane sheath, closed at one end, with flexible rings at both ends. The device is inserted into the vagina by compressing the inner ring and pushing it in. Properly positioned, the ring at the closed end covers the cervix, and the sheath lines the walls of the vagina. The outer ring remains outside the vagina, covering the labia. (Med Lett Drugs Ther 1993 Dec 24;35(12):123)
A potent HIV protease inhibitor. It is used in combination with other antiviral drugs in the treatment of HIV in both adults and children.
Community Health Services
The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.
The purified, alkaloidal, extra-potent form of cocaine. It is smoked (free-based), injected intravenously, and orally ingested. Use of crack results in alterations in function of the cardiovascular system, the autonomic nervous system, the central nervous system, and the gastrointestinal system. The slang term "crack" was derived from the crackling sound made upon igniting of this form of cocaine for smoking.
Renal syndrome in human immunodeficiency virus-infected patients characterized by nephrotic syndrome, severe proteinuria, focal and segmental glomerulosclerosis with distinctive tubular and interstitial changes, enlarged kidneys, and peculiar tubuloreticular structures. The syndrome is distinct from heroin-associated nephropathy as well as other forms of kidney disease seen in HIV-infected patients.
Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.
Vaginal Creams, Foams, and Jellies
Medicated dosage forms for topical application in the vagina. A cream is a semisolid emulsion containing suspended or dissolved medication; a foam is a dispersion of a gas in a medicated liquid resulting in a light, frothy mass; a jelly is a colloidal semisolid mass of a water soluble medicated material, usually translucent.
A republic in the Greater Antilles in the West Indies. Its capital is Port-au-Prince. With the Dominican Republic it forms the island of Hispaniola - Haiti occupying the western third and the Dominican Republic, the eastern two thirds. Haiti belonged to France from 1697 until its rule was challenged by slave insurrections from 1791. It became a republic in 1820. It was virtually an American protectorate from 1915 to 1934. It adopted its present constitution in 1964 and amended it in 1971. The name may represent either of two Caribbean words, haiti, mountain land, or jhaiti, nest. (From Webster's New Geographical Dictionary, 1988, p481 & Room, Brewer's Dictionary of Names, 1992, p225)
The insertion of drugs into the vagina to treat local infections, neoplasms, or to induce labor. The dosage forms may include medicated pessaries, irrigation fluids, and suppositories.