Estimating HIV incidence among female partners of bisexual men in China

Background: HIV prevalence among men who have sex with men (MSM) in China is rapidly increasing. The majority of Chinese MSM engage in bisexual behaviors and their female partners may be at high risk of HIV infection.

Methods: Through a comprehensive literature review and the utilization of a mathematical optimization approach, this study infers quantitative distributions of sexual behavioral practices between Chinese MSM and their female partners over the past decade, and consequently estimates the trends in HIV incidence rates among female partners of Chinese MSM.

Results: The average Chinese MSM had approximately 0.89 (95% confidence interval (CI) 0.68-1.23) female sexual partners, with a mean number of total penetrative acts with the female partners of 0.57 (95% CI 0.52-0.62), in the past 6 months. Condom usage increased slightly from 23.57% (95% CI 14.20-32.93%) in 2002 to 27.33% (95% CI 19.88-34.78%) in 2010. Thus, the substantially increasing HIV prevalence among MSM has led to an increase in HIV incidence among partners of bisexual MSM of approximately 5.3-fold, from 0.18 per 1000 person-years in 2002 to 0.88 per 1000 person-years in 2010.

Conclusions: Bisexual Chinese MSM may be a bridge group to the general female population for HIV transmission. There has been a substantial HIV incidence increase among their female partners.