HIV SeropositivityHIV SeroprevalenceHIV InfectionsDisease ProgressionAcquired Immunodeficiency SyndromeSubstance Abuse, IntravenousSexual BehaviorHIV-1Risk FactorsSeroepidemiologic StudiesViral LoadSimian Acquired Immunodeficiency SyndromeSimian immunodeficiency virusnef Gene Products, Human Immunodeficiency VirusMorbidityCohort StudiesMacaca mulattaCD4-Positive T-LymphocytesAntibodies, ViralAntibodies, BacterialChlamydophila pneumoniaeImmunoglobulin GChlamydophila InfectionsPrevalenceEnzyme-Linked Immunosorbent AssaySerologic TestsHIV SeronegativityHelicobacter pyloriHelicobacter InfectionsCross-Sectional StudiesProspective StudiesTime FactorsCytomegalovirus InfectionsToxocariasisAntibodies, ProtozoanAIDS SerodiagnosisRetrospective StudiesTreatment OutcomeFollow-Up StudiesAge FactorsCase-Control StudiesToxoplasmosisHepatitis CCD4 Lymphocyte CountHerpesvirus 2, HumanToxocaraRural PopulationBlood DonorsBrazilIncidencePapillomavirus InfectionsHomosexualityAIDS-Related Opportunistic InfectionsOdds RatioCytomegalovirusAnti-HIV AgentsNeosporaPregnancyMultivariate AnalysisSyphilisHerpes GenitalisImmunoglobulin ALogistic ModelsInfant, NewbornToxoplasmaIndiaHuman papillomavirus 16United StatesCell CycleImmunoglobulin MRisk-TakingPrognosisHomosexuality, MaleSexual PartnersHepatitis A Virus, HumanHIV AntigensHepatitis BAntibodies, Helminth