Nevirapine: A potent, non-nucleoside reverse transcriptase inhibitor used in combination with nucleoside analogues for treatment of HIV INFECTIONS and AIDS.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.Reverse Transcriptase Inhibitors: Inhibitors of reverse transcriptase (RNA-DIRECTED DNA POLYMERASE), an enzyme that synthesizes DNA on an RNA template.Infectious Disease Transmission, Vertical: The transmission of infectious disease or pathogens from one generation to another. It includes transmission in utero or intrapartum by exposure to blood and secretions, and postpartum exposure via breastfeeding.Benzoxazines: OXAZINES with a fused BENZENE ring.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syndrome (AIDS).Zidovudine: A dideoxynucleoside compound in which the 3'-hydroxy group on the sugar moiety has been replaced by an azido group.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.Stavudine: A dideoxynucleoside analog that inhibits reverse transcriptase and has in vitro activity against HIV.Pregnancy Complications, Infectious: The co-occurrence of pregnancy and an INFECTION. The infection may precede or follow FERTILIZATION.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.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.Lamivudine: A reverse transcriptase inhibitor and ZALCITABINE analog in which a sulfur atom replaces the 3' carbon of the pentose ring. It is used to treat HIV disease.Plasma: The residual portion of BLOOD that is left after removal of BLOOD CELLS by CENTRIFUGATION without prior BLOOD COAGULATION.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.Lopinavir: An HIV protease inhibitor used in a fixed-dose combination with RITONAVIR. It is also an inhibitor of CYTOCHROME P-450 CYP3A.Oxazines: Six-membered heterocycles containing an oxygen and a nitrogen.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.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.Oxidoreductases, N-DemethylatingAnti-Retroviral Agents: Agents used to treat RETROVIRIDAE INFECTIONS.PyrimidinonesCD4 Lymphocyte Count: The number of CD4-POSITIVE T-LYMPHOCYTES per unit volume of BLOOD. Determination requires the use of a fluorescence-activated flow cytometer.Uganda: A republic in eastern Africa, south of SUDAN and west of KENYA. Its capital is Kampala.Exanthema: Diseases in which skin eruptions or rashes are a prominent manifestation. Classically, six such diseases were described with similar rashes; they were numbered in the order in which they were reported. Only the fourth (Duke's disease), fifth (ERYTHEMA INFECTIOSUM), and sixth (EXANTHEMA SUBITUM) numeric designations survive as occasional synonyms in current terminology.Drug Therapy, Combination: Therapy with two or more separate preparations given for a combined effect.Ritonavir: An HIV protease inhibitor that works by interfering with the reproductive cycle of HIV. It also inhibits CYTOCHROME P-450 CYP3A.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Burundi: A republic in eastern Africa bounded on the north by RWANDA and on the south by TANZANIA. Its capital is Bujumbura.Zambia: A republic in southern Africa, south of DEMOCRATIC REPUBLIC OF THE CONGO and TANZANIA, and north of ZIMBABWE. Its capital is Lusaka. It was formerly called Northern Rhodesia.Treatment Failure: A measure of the quality of health care by assessment of unsuccessful results of management and procedures used in combating disease, in individual cases or series.Delavirdine: A potent, non-nucleoside reverse transcriptase inhibitor with activity specific for HIV-1.Botswana: A republic in southern Africa, between NAMIBIA and ZAMBIA. It was formerly called Bechuanaland. Its capital is Gaborone. The Kalahari Desert is in the west and southwest.Drug Eruptions: Adverse cutaneous reactions caused by ingestion, parenteral use, or local application of a drug. These may assume various morphologic patterns and produce various types of lesions.Malawi: A republic in southern Africa east of ZAMBIA and MOZAMBIQUE. Its capital is Lilongwe. It was formerly called Nyasaland.Milk, HumanRNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Breast Feeding: The nursing of an infant at the breast.Dried Blood Spot Testing: Techniques for using whole blood samples collected on filter paper for a variety of clinical laboratory tests.Infant, Newborn: An infant during the first month after birth.HIV Protease Inhibitors: Inhibitors of HIV PROTEASE, an enzyme required for production of proteins needed for viral assembly.Organophosphonates: Carbon-containing phosphonic acid compounds. Included under this heading are compounds that have carbon bound to either OXYGEN atom or the PHOSPHOROUS atom of the (P=O)O2 structure.South Africa: A republic in southern Africa, the southernmost part of Africa. It has three capitals: Pretoria (administrative), Cape Town (legislative), and Bloemfontein (judicial). Officially the Republic of South Africa since 1960, it was called the Union of South Africa 1910-1960.Drug Interactions: The action of a drug that may affect the activity, metabolism, or toxicity of another drug.Aryl Hydrocarbon Hydroxylases: A large group of cytochrome P-450 (heme-thiolate) monooxygenases that complex with NAD(P)H-FLAVIN OXIDOREDUCTASE in numerous mixed-function oxidations of aromatic compounds. They catalyze hydroxylation of a broad spectrum of substrates and are important in the metabolism of steroids, drugs, and toxins such as PHENOBARBITAL, carcinogens, and insecticides.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.Indinavir: A potent and specific HIV protease inhibitor that appears to have good oral bioavailability.Cote d'Ivoire: 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.Nelfinavir: A potent HIV protease inhibitor. It is used in combination with other antiviral drugs in the treatment of HIV in both adults and children.Didanosine: A dideoxynucleoside compound in which the 3'-hydroxy group on the sugar moiety has been replaced by a hydrogen. This modification prevents the formation of phosphodiester linkages which are needed for the completion of nucleic acid chains. Didanosine is a potent inhibitor of HIV replication, acting as a chain-terminator of viral DNA by binding to reverse transcriptase; ddI is then metabolized to dideoxyadenosine triphosphate, its putative active metabolite.Drug-Induced Liver Injury: A spectrum of clinical liver diseases ranging from mild biochemical abnormalities to ACUTE LIVER FAILURE, caused by drugs, drug metabolites, and chemicals from the environment.Ligase Chain Reaction: A DNA amplification technique based upon the ligation of OLIGONUCLEOTIDE PROBES. The probes are designed to exactly match two adjacent sequences of a specific target DNA. The chain reaction is repeated in three steps in the presence of excess probe: (1) heat denaturation of double-stranded DNA, (2) annealing of probes to target DNA, and (3) joining of the probes by thermostable DNA ligase. After the reaction is repeated for 20-30 cycles the production of ligated probe is measured.Adenine: A purine base and a fundamental unit of ADENINE NUCLEOTIDES.