Who are the sexual partners of transgender individuals? Differences in demographic characteristics and risk behaviours of San Francisco HIV testing clients with transgender sexual partners compared with overall testers

Background: Research to examine the sexual networks of transgender people may be the key to understanding why transwomen are at high risk of contracting HIV. Methods: Bivariate and multivariate analysis of San Francisco HIV county counselling and testing data from 2010 was conducted to compare demographic factors and risk behaviours of the partners of transgender people (PTG) to HIV testing clients overall. Results: Of the 13 754 clients overall, 477 reported having sex with a transgender person in the past 12 months. PTG were significantly more likely to be transgender, Latino, multiracial or 'other', and identify as bisexual. In multivariate analyses, PTG were significantly more likely to have used and injected drugs in the past 12 months; in bivariate analysis, PTG had a significantly higher likelihood of having unprotected vaginal or anal sex. PTG who had engaged in vaginal or anal sex in the past 12 months had an HIV positivity of 0.6% compared with 1.1% for non-PTG. Conclusions: People who report having transgender sexual partners engage in higher-risk behaviours than other HIV testers yet had a lower HIV positivity. Potential explanations for the discrepancy between higher-risk behaviours and lower HIV positivity for PTG may be engagement in HIV-protective behaviours like regular HIV testing and lower risk seropositioning being the insertive sexual partner. Future studies on the sexual networks of transgender people, and sexual and risk behaviours of PTG may elucidate the HIV risk for both PTG and their transgender partners.