A potential source for the transmission of the human immunodeficiency virus into the heterosexual population: bisexual men who frequent "beats".

Fifty-four actively bisexual men with recent sexual experiences with both men and women were interviewed as part of a wider study of 176 homosexual men, many of whom frequented "beats" (public toilets, parks and isolated roads where men meet for homosexual encounters). Forty-six per cent of the bisexual men were engaging in unsafe sexual practices with at least one man and one woman. Three of these men knew that they were seropositive for the human immunodeficiency virus, with two of these men engaging in unsafe sexual practices with some of their partners. Fewer than one-quarter of the bisexual men identified with or participated actively in aspects of organized, overt "gay" culture. So-called "closeted" bisexual men are suggested to be a major, but neglected, target for educational efforts against the acquired immunodeficiency syndrome.