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Background: Men who have sex with men (MSM) remain the group most affected by the HIV epidemic in the United States. At least one-quarter of MSM report engagement in group sex events (GSEs), which can pose a risk for HIV transmission and acquisition. In this study, we sought to identify event-level correlates of sexual and drug use behaviors at GSEs to better inform prevention activities.

Methods: For this study, we recruited participants via banner and pop-up advertisements placed on a geosocial networking mobile phone application for MSM to meet.

Results: Of the 1,997 individuals who completed the study screener, 36.0% reported participating in at least one GSE in the prior year. In multivariable logistic regression, attendance at a GSE in the past year was significantly associated with older age, full/part time employment, and being HIV-positive. Of the men who attended a GSE, more than half reported condomless anal sex (CAS) with at least one of their partners (insertive: 57.7%; receptive: 56.3%). MSM who indicated drug use had significantly higher odds of having insertive CAS (odds ratio (OR) = 2.45; 95% confidence interval (CI): 1.37, 4.39) and receptive CAS (OR = 3.60; 95% CI: 1.96, 6.63) at their last GSE.

Conclusions: The high prevalence of HIV-positive MSM engaging in group sex, coupled with their greater odds of CAS, poses a significant risk for HIV/STI transmission within the group sex setting. More research is needed to determine patterns of condom use at these events, and whether seroadaptive behaviors are driving CAS.


This is the accepted manuscript of an article published in Sexual Health.



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