Blue-Ribbon Boys: factors associated with PrEP use, ART use and undetectable viral load among gay app users across six regions of the world.

INTRODUCTION: Gay social networking apps have grown in popularity among men who have sex with men offering opportunities for rapid and confidential collection of vital data as well as social connection. The goal of our study was to explore factors associated with utilization of pre-exposure prophylaxis (PrEP) and antiretroviral treatment (ART), and self-reported undetectable viral load (UVL) using data collected by the gay social networking app Hornet. METHODS: In 2016, the Global Forum on MSM & HIV (MSMGF) partnered with Hornet, to support an educational initiative called Blue-Ribbon Boys. One aspect of the initiative prompts Hornet users to answer a short series of yes-no questions about their sexual health. Using survey responses, we evaluated factors associated with PrEP and ART use as well as self-reported UVL by fitting separate multivariable generalized estimating equation models. RESULTS: In total, 16,008 unique Hornet users started the survey, of which 12,126 (76%) provided sufficient data for analyses. Of the 10,774 HIV-negative men, 13% reported PrEP use in the past year. PrEP use was associated with a recent sexually transmitted infection (STI) test or treatment (aOR = 2.19, CI = 1.49 to 3.21); and taking steps to protect oneself from HIV (aOR = 1.41, CI = 1.13 to 1.76). Among HIV-positive Hornet users (n = 1243), ART use was associated with older age (each year increase aOR = 1.02, CI = 1.01 to 1.04), a recent STI test or treatment (aOR = 4.54, CI = 2.65 to 7.78); and awareness of unlikely HIV transmission with UVL (aOR = 1.53, CI = 1.03 to 2.26). UVL was associated with older age (each year increase aOR = 1.03, CI = 1.01 to 1.04), a recent STI test or treatment (aOR = 4.84, CI = 2.74 to 8.55), and awareness of unlikely HIV transmission with UVL (aOR = 1.98, CI = 1.37 to 2.85). CONCLUSIONS: Study findings underscore the importance of STI testing and treatment as well as information about HIV transmissibility for encouraging PrEP and ART use. Our findings also reveal age disparities, which can undermine incidence reduction among gay men. Gay social networking apps can be effectively used for rapid data collection and sexual health promotion with men who have sex with men. STI testing and treatment programmes offer important opportunities for encouraging PrEP and ART use. Information about HIV transmissibility with consistent ART use should be incorporated into prevention messaging tailored to various age groups.