San Franciscan MSM have similar types and numbers of partnerships with men inside San Francisco and outside San Francisco, 2011.

Sexual networks among men who have sex with men (MSM) across health jurisdictions may play a role in HIV transmission and acquisition. Levels of HIV prevention activities may be different across health jurisdictions leading to differential risk for HIV transmission with partners in and outside of San Francisco (SF). We examined MSM sexual partnerships within and outside SF. Data were collected during the 2011 National HIV Behavioral Surveillance MSM data collection cycle. Participants were asked to report characteristics of and sexual behaviors with up to five most recent sexual partners. Restricting our analysis to sexually active San Franciscans (n = 329 MSM reporting 927 partnerships), we found that SF MSM have similar numbers of partnerships (SF mean = 1.3, non-SF mean = 1.2) and levels of risk behavior with men within and outside SF. With the current intensity of HIV prevention occurring in SF additional strategies may be needed to address the fact that SF MSM have many sexual connections to men in other health jurisdictions where HIV prevention may not be similar to those in SF.