The truth, of course, is that anyone can contract HIV, given the right circumstance, and according to the Yale University Library's online exhibition " We Are Everywhere: Lesbians in the Archive," by 1991 roughly 40% of HIV-positive people and 12% of AIDS patients in the U.S. were women. But a combination of longstanding bias in the medical field and the perception of HIV/AIDS as a gay epidemic led to women being excluded from research studies and clinical trials.