Seroadaptation among men who have sex with men: emerging research themes

Abstract

Seroadaptation describes a diverse set of potentially harm-reducing behaviors that use HIV status to inform sexual decision making. Men who have sex with men (MSM) in many settings adopt these practices, but their effectiveness at preventing HIV transmission is debated. Past modeling studies have demonstrated that serosorting is only effective at preventing HIV transmission when most men accurately know their HIV status, but additional modeling is needed to address the effectiveness of broader seroadaptive behaviors. The types of information withwhichMSMmake seroadaptive decisions is expanding to include viral load, treatment status, and HIV status based on home-use tests, and recent research has begun to examine the entire seroadaptive process, from an individual's intentions to seroadapt to their behaviors to their risk of acquiring or transmitting HIV and other STIs. More research is needed to craft clear public health messages about the risks and benefits of seroadaptive practices.

Fig. 1

Estimated relationship between serosorting, testing frequency, and HIV prevalence from a model simulation of HIV transmission dynamics among men who have sex with men. Serosorting is predicted to have little impact on equilibrium HIV prevalence or risk of HIV acquisition when low- and high-activity MSM test every 3 and 1.5 years, respectively. Serosorting is potentially protective at high testing frequencies and has a small deleterious effect at lower testing frequencies. Low-activity men are defined as having 1 anal sex partner per year, and high-activity men are defined as having an average of 10 anal sex partners per year. Data for the model are from 2003 random-digit-dial study of MSM in Seattle. The figure is adapted from a previously published model of serosorting among MSM [62, 65]