New research challenges the popular assumption that bisexual men are responsible for significant HIV transmission to their female partners.
The number of HIV-positive men who have sex with both men and women is likely no higher than the number of HIV positive heterosexual men, according to the US-based analysis.
The findings, presented at the American Public Health Association’s 141st Annual Meeting & Exposition in Boston, build a case for federal investment in research on HIV prevalence among bisexually behaving men.
“Some observers have exaggerated the idea of viral ‘bridging’—where a bisexual man contracts HIV from another man and then transmits it to a female partner. But, at least in the US, the data supporting the extent of this is quite limited,” says Mackey R. Friedman, of the University of Pittsburgh Public Health’s department of infectious diseases and microbiology, who led the research.
Currently, the US Centers for Disease Control and Prevention (CDC) does not report on HIV data specific to bisexually behaving people, though it does report data on homosexually and heterosexually behaving people, as well as injection drug users.
Friedman and his colleagues reviewed over 3,000 scientific articles to obtain data on HIV prevalence and risks among men who have sex with men only and men who have sex with men and women.
The bisexually behaving men were only 40 percent as likely to be infected with HIV as the homosexually behaving men. The researchers propose that this is because the bisexually behaving men reported lower rates of unprotected receptive anal intercourse, the biggest risk factor for HIV transmission among men in the US.
The analysis also estimates that there are approximately 1.2 million bisexual men in the US, of whom 121,800 are HIV-positive. That estimate aligns with CDC estimates for HIV infection in male heterosexuals and intravenous drug users.
Friedman believes that while bisexually behaving men may have a lower risk profile than homosexually behaving men, their HIV burden still warrants the development of targeted interventions.
“The HIV infection risk that bisexual men pose to their female partners has likely been overstated,” says Friedman. “However, that doesn’t mean that HIV-prevention campaigns targeting bisexual men and their male and female partners aren’t needed. HIV does exist in the bisexual community, and national, bisexual-specific data collection, research, and HIV prevention and care delivery are necessary to ameliorate this population’s HIV burden.”
Source: University of Pittsburgh