Distribution of Behavioral Patterns Before Infection Among San Francisco Men Who Have Sex With Men Newly Infected With HIV in 2014

Risk assessment for HIV infection in men who have sex with men and the contribution of sexual partner networks

This study aimed to evaluate the risk of HIV infection in men who have sex with men (MSM) by developing an index that considers sex partner networks. The index variables were age, ethnicity/skin color, schooling, relationship type, condom use in receptive and insertive relationships, self-perception of the possibility of HIV infection, sexually transmitted infections, and rapid HIV testing results. We used data from a cross-sectional MSM egocentric network survey conducted in Rio de Janeiro between 2014 and 2015. The initial research volunteer is called ego, each partner is called alter, and each pair of people in a relationship is called the dyad. Multiple logistic regression was used to define the coefficients of the equations for the elaboration of the indices. The index ranged from 0 to 1; the closer to 1, the higher the risk of HIV infection. HIV prevalence was 13.9% among egos. The mean egos index with an HIV-reactive test was 57% higher than non-reactive, and the same profile was observed in the index values of dyads. The index allowed the incorporation of network data through the dyads and contributed to the identification of individuals with a higher likelihood of acquiring HIV.

Increases in Pre-exposure Prophylaxis Use and Decreases in Condom Use: Behavioral Patterns Among HIV-Negative San Francisco Men Who have Sex with Men, 2004-2017

Using data from the National HIV Behavioral Surveillance of men who have sex with men (MSM), we estimated the prevalence of sexual behaviors among HIV-negative San Francisco MSM between 2004 and 2017. We estimate a recent increase in the 1-year prevalence of pre-exposure prophylaxis (PrEP) use, from 9.8% in 2014 to 44.9% in 2017. Over that same period, we estimate a decrease in the prevalence of consistent condom use, from 18.5 to 9.4%, and an increase in the percent of individuals with multiple condomless anal intercourse partners. We conclude that while risks for HIV infection may be decreasing among San Francisco MSM due, in part, to increases in PrEP use, the population faces increased risks for other sexually transmitted infections (STIs). Because PrEP alone does not protect against other STIs, we strongly recommend that PrEP users use condoms when possible, routinely screen for STIs, and disclose infections with sexual partners.