Human immunodeficiency virus type 1 infection in homosexual men who remain seronegative for prolonged periods.
D015492:AIDS Serodiagnosis; D002353:Carrier State; D005260:Female; D015658:HIV Infections / Q000635:transmission*; D006679:HIV Seropositivity; D006716:Homosexuality; D006801:Humans; D008297:Male; D013997:Time Factors