Heterosexual transmission of HIV--Puerto Rico, 1981-1991.
D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology / Q000635:transmission*; D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D011647:Puerto Rico / Q000453:epidemiology; D012309:Risk-Taking; D012725:Sexual Behavior