HIV InfectionsEndogenous RetrovirusesRetroviridaeHIV SeropositivityHIV-1Retroviridae InfectionsHIV SeroprevalenceAcquired Immunodeficiency SyndromeHIVAnti-HIV AgentsHIV SeronegativityAIDS SerodiagnosisRetroviruses, SimianLeukemia Virus, MurineSexual BehaviorCD4 Lymphocyte CountProvirusesTerminal Repeat SequencesBetaretrovirusHomosexuality, MaleSpumavirusGene Products, gagMolecular Sequence DataVirus ReplicationRNA, ViralAnti-Retroviral AgentsViral LoadRisk-TakingVirus IntegrationSubstance Abuse, IntravenousAIDS-Related Opportunistic InfectionsSimian foamy virusBase SequenceRetroviridae ProteinsPrevalenceCell LineSouth AfricaRetroelementsDNA, ViralAntiretroviral Therapy, Highly ActiveHIV AntigensSexual PartnersGenes, polRNA-Directed DNA PolymeraseGenes, gagCD4-Positive T-LymphocytesGenes, envRisk FactorsGenetic VectorsMoloney murine leukemia virusHIV Core Protein p24HIV-2GammaretrovirusGene Products, envAIDS Dementia ComplexProstitutionZimbabweAmino Acid SequenceHIV Protease InhibitorsCondomsMason-Pfizer monkey virusHomosexualityInfectious Disease Transmission, VerticalGenes, Intracisternal A-ParticleUnsafe SexHIV AntibodiesGenes, ViralCross-Sectional StudiesHIV Reverse TranscriptaseGene Products, polVirionHIV Envelope Protein gp120UgandaReceptors, VirusAlpharetrovirusSyphilisPregnancy Complications, InfectiousPhylogenyHeterosexualityAvian leukosis virusViral Envelope ProteinsGene Expression Regulation, ViralAfrica South of the SaharaMalawiSimian immunodeficiency virusCoinfectionCytidine DeaminaseAvian Sarcoma VirusesCohort StudiesAIDS-Related Complexgag Gene Products, Human Immunodeficiency VirusRepetitive Sequences, Nucleic AcidZidovudineUnited StatesReticuloendotheliosis virusGenome, ViralHIV Wasting SyndromeCounselingReverse TranscriptionCircumcision, Male