title: HIV may have surfaced in U.S. as early as 1969, scientist says.
mesh_terms: D000293:Adolescent; D006678:HIV / Q000302:isolation & purification*; D015658:HIV Infections / Q000453:epidemiology*; D006801:Humans; D008297:Male; D012514:Sarcoma, Kaposi / Q000821:virology*; D014481:United States / Q000453:epidemiology