Willingness to use and distribute HIV self-testing kits among people who inject drugs in the San Diego–Tijuana border region

Abstract

Abstract Background HIV self-testing (HIVST) could increase HIV testing access among people who inject drugs (PWID), and secondary distribution (i.e., peer-delivery) of HIVST kits in PWID social networks could further expand coverage. We assessed willingness to use and distribute HIVST kits among PWID in the San Diego–Tijuana border region. Methods From 2020 to 2021, HIV-negative PWID in San Diego, USA, and Tijuana, Mexico, completed surveys and provided data on individual (N = 539) and social network (N = 366) characteristics. We used modified Poisson regression to examine the effects of individual and social network characteristics on willingness to use and distribute HIVST kits. Results Most participants were willing to use (81%) and distribute (81%) HIVST kits. At the individual level, prior HIV testing was positively associated with willingness to use (adjusted prevalence ratio [aPR] = 1.24, 95% confidence interval [CI] 1.10–1.40) and distribute (aPR = 1.27, 95% CI 1.12–1.43) HIVST kits, while perceiving oneself to be at higher HIV risk than others was negatively associated with willingness to use HIVST kits (aPR = 0.83, 95% CI 0.74–0.93). At the network level, willingness to distribute HIVST kits was positively associated with network size (aPR = 1.04 per member, 95% CI 1.01–1.08) and greater proportions of one’s network encouraging them to use drugs (aPR = 1.29, 95% CI 1.16–1.44) and having a history of homelessness (aPR = 1.51, 95% CI 1.31–1.74) or detention/arrest (aPR = 1.57, 95% CI 1.36–1.82), and negatively associated with a greater proportion of one’s network including “very close” persons (aPR = 0.80, 95% CI 0.69–0.94). Conclusions We found high potential for HIVST kits and their secondary distribution to increase HIV testing among PWID who face the greatest barriers to facility-based testing.