HIV InfectionsHIV-1HIVViral LoadChronic DiseaseAntiretroviral Therapy, Highly ActiveAnti-HIV AgentsCD4 Lymphocyte CountCD4-Positive T-LymphocytesViremiaCD8-Positive T-LymphocytesVirus ReplicationHIV SeropositivityHIV SeroprevalenceRNA, ViralAcquired Immunodeficiency SyndromeHIV SeronegativityAIDS SerodiagnosisDisease ProgressionSexual BehaviorHomosexuality, MaleRisk-TakingAnti-Retroviral AgentsSubstance Abuse, IntravenousAIDS-Related Opportunistic InfectionsPrevalenceSouth AfricaSexual PartnersHIV AntigensRisk FactorsAIDS Dementia ComplexProstitutionZimbabweHIV Protease InhibitorsCondomsHIV Core Protein p24HomosexualityInfectious Disease Transmission, VerticalUnsafe SexCross-Sectional StudiesUgandaSyphilisPregnancy Complications, InfectiousHeterosexualityHIV AntibodiesHIV Envelope Protein gp120Africa South of the SaharaMalawiCoinfectionCohort StudiesAIDS-Related ComplexUnited StatesHIV Wasting SyndromeCounselingCircumcision, MaleReceptors, HIVSafe SexHealth Knowledge, Attitudes, PracticeReceptors, CCR5Sexually Transmitted DiseasesIncidenceVoluntary ProgramsPregnancyZidovudineEpidemicsHIV-2Population SurveillanceHIV Reverse TranscriptaseHIV Long-Term SurvivorsTuberculosisSubstance-Related DisordersZambiaMass ScreeningTanzaniaHIV EnteropathyNeedle SharingAntigens, CD4Sex WorkersHepatitis CSexually Transmitted Diseases, ViralHIV ProteasePrisonersIndiaKenyaRural PopulationCenters for Disease Control and Prevention (U.S.)RwandaProspective StudiesSocioeconomic FactorsSimian Acquired Immunodeficiency SyndromeDrug Resistance, ViralNew York CityLogistic ModelsAfricaTime FactorsOrganophosphonates