If promiscuity were a cause of AIDS, one would have expected cases to have occurred among prostitutes (male or female) prior to 1978. Reports of such cases are lacking, even though prostitution has been present in most if not all cultures throughout history.

In this country, trends in gonorrheal infections suggest that extramarital sexual activity was extensive in the pre-AIDS era. Cases of gonorrhea in the United States peaked at approximately 1 million in 1978; between 250,000 and 530,000 cases were reported each year in the 1960s, approximately 250,000 cases each year in the 1950s, and between 175,000 and 380,000 cases annually in the 1940s (CDC, 1987c, 1993b). Despite the frequency of sexually transmitted diseases, only a handful of documented cases of AIDS in the United States prior to 1978 have been reported.

Historians, archaeologists and sociologists have documented extensive homosexual activity dating from the ancient Greeks to the well-established homosexual subculture in the United States in the 20th century (Weinberg and Williams, 1974; Gilbert, 1980-81; Saghir and Robins, 1973; Reinisch et al., 1990; Doll et al., 1990; Katz, 1992; Friedman and Downey, 1994). Depictions of anal intercourse, both male and female, can be found in the art and literature of numerous cultures on all inhabited continents (Reinisch et al., 1990). In the 1940s, Kinsey et al. reported that 37 percent of all American males surveyed had at least some overt homosexual experience to the point of orgasm between adolescence and old age and that 10 percent of men were exclusively or predominantly homosexual between the ages of 16 and 55 (Kinsey et al., 1948). More recent surveys have found that 2 to 5 percent of men are homosexual or bisexual (reviewed in Friedman and Downey, 1994; Seidman and Rieder, 1994; Laumann, 1994).

Many homosexuals had multiple sexual partners in the pre-AIDS era: a 1969 survey found that more than 40 percent of white homosexual males and one-third of black homosexual males had at least 500 partners in their lifetime, and an additional one-fourth reported between 100 and 500 partners (Bell and Weinberg, 1978). A majority of these men reported that more than half their partners had been strangers before the sexual encounters (Bell and Weinberg, 1978). Further evidence of extensive homosexual behavior in the years preceding the AIDS epidemic comes from reports of numerous cases of rectal gonorrheal and anal herpes simplex virus infections among men (Jefferiss, 1956; Scott and Stone, 1966; Pariser and Marino, 1970; Owen and Hill, 1972; British Cooperative Clinical Group, 1973; Jacobs, 1976; Judson et al., 1977; Merino and Richards, 1977; McMillan and Young, 1978).