Modelling the UNAIDS 90-90-90 treatment cascade for gay, bisexual and other men who have sex with men in South Africa: using the findings of a data triangulation process to map a way forward.

A data triangulation exercise was carried out between 2013 and 2015 to assess the HIV epidemic and response among gay, bisexual and other men who have sex with men (GBMSM) in South Africa. We used the findings to assess progress in achieving the UNAIDS 90-90-90 goals for GBMSM in the country. Three scenarios were developed using different GBMSM population factors (2.0, 3.5 and 5.0% of males aged ≥15) to estimate the population size, HIV prevalence of 13.2-49.5%, and 68% of GBMSM knowing their status. Due to data gaps, general population data were used as estimates of GBMSM on antiretroviral therapy (ART) and virologically suppressed (25.7 and 84.0%, respectively). The biggest gap is access to ART. To address the data gap we recommend developing data collection tools, indicators, and further quantification of HIV cascades. Targeted testing, linkage to services and scaled-up prevention interventions (including pre-exposure prophylaxis) are also required.