Secondary Distribution of Dual HIV/Syphilis Self-Testing Among Men Who Have Sex With Men: Pragmatic Randomized Controlled Trial in China.

Background: The World Health Organization recommends dual HIV/syphilis testing, but this approach has not been examined in many low- and middle-income countries. Dual HIV/syphilis self-testing may accelerate secondary distribution of self-test kits. Preliminary studies in Guangdong, China, have demonstrated the feasibility and cost-effectiveness of dual HIV/syphilis self-testing distribution via social media, but evidence comparing dual HIV/syphilis self-testing to single HIV self-testing for secondary distribution within social networks remains limited in resource-limited settings.

Objective: We aimed to evaluate the effectiveness of secondary distribution of dual HIV/syphilis self-testing kits in promoting HIV testing uptake among men who have sex with men (MSM) in China.

Methods: We conducted a pragmatic 3-arm randomized controlled study in the Guangxi Zhuang Autonomous Region, China. MSM aged 18 years or older who were HIV-negative were enrolled and randomly assigned (1:1:1) to either the site-based HIV testing (SBT) group (110/330, 33.3%), single HIV self-testing (SST) group (110/330, 33.3%), or dual HIV/syphilis self-testing (DST) group (110/330, 33.3%). Participants in the SST and DST groups received free finger-prick-based HIV self-testing or HIV/syphilis self-testing kits at enrollment and during the 12-month follow-up. The primary outcome was the mean number of social network members motivated by the participant and the mean frequency of HIV tests per participant within a 3-month period. The data were analyzed using an intention-to-treat analysis.

Results: A total of 330 MSM were recruited, among whom 319 (319/330, 96.7%) completed at least 1 follow-up survey and were subsequently included in the analysis. Among the participants, 245/319 (77%) had a college education or above. Compared to social network members in the SBT group, those in the intervention SST and DST groups were more likely to motivate others for HIV testing over a 3-month average duration. The mean number of motivated individuals was 0.42 in the SST group versus 0.20 in the SBT group, a mean difference (MD) of 0.22 (95% CI 0.12-0.33; P<.001). The mean was 0.51 in the DST group versus 0.20 in the SBT group, with an MD of 0.32 (95% CI 0.20-0.43; P<.001). The mean frequency of total HIV tests per participant in the SST group (1.33) was higher than that in the SBT group (0.87), with an MD of 0.46 (95% CI 0.31-0.62; P<.001) over 3 months. Over a 3-month period, the mean number of HIV tests per participant was higher in the DST group (1.43) than in the SBT group (0.87), with an MD of 0.57 (95% CI 0.41-0.73; P<.001). A total of 4 (1.3%) individuals had a new HIV positive result, while 11 (3.4%) had a new syphilis positive result. All individuals who had positive self-test results underwent laboratory-based confirmation tests. There were no adverse events reported.

Conclusions: Our data demonstrate that the secondary distribution strategy of HIV/syphilis self-testing proves to be an effective means of expanding HIV testing coverage by encouraging the distribution of testing kits within the social networks of MSM.

Trial registration: Chinese Clinical Trial Registry ChiCTR2100050898; https://www.chictr.org.cn/hvshowproject.html?id=158876.