Home-based HIV testing: Using different strategies among transgender women in Argentina.

Background: In Argentina, HIV prevalence among transgender women (TGW) has been reported at 34%. The stigma is one of the most important factors limiting their access to healthcare services. The aims of this study were to compare different HIV testing methodologies, to determine the factors associated with HIV diagnosis and to determine the feasibility of a home-based HIV testing service for TGW.

Methods: A multidisciplinary team performed home-based HIV testing interventions in four cities of Argentina. Participants self-identified as TGW, older than 14 years and with a negative or unknown HIV status. Blood samples were screened by two rapid tests (RT), one based on antibodies (Determine™ HIV-1/2) and the other on antigen and antibodies (Determine™ HIV-1/2 Combo), and the subsequent blood processing via 4th generation ELISA (VIDAS HIV DUO). All reactive samples were confirmed with a viral load (VL). We compared the results of both RT with the ELISA. Samples were pooled in groups of 6 and a VL (Abbott Real Time) performed to identify acute HIV infections. Factors associated with HIV infection were evaluated with multivariate logistic regression analysis.

Results: A total of 260 TGW were tested, 51 tested positive (HIV prevalence 19.6%). There were no discordant results between both RTs nor between RTs and 4th generation ELISA, therefore the correlation was 100%. The VL identified 2 additional positive samples. The final analytic sample for positive cases consisted of 53 TGW. In the multivariate analysis, factors associated with a positive HIV result were history of other sexually transmitted infections (STIs) and not being previously tested for HIV. TGW tested for the first time were at 4 times greater risk of being HIV positive compared to those that were tested previously.

Conclusions: A multidisciplinary home-based HIV testing service among TGW is feasible and effective to detect cases of HIV infection. The testing algorithm should start with an RT followed by molecular diagnosis. The history of STIs and never having been tested for HIV were the factors associated with HIV-positive results and should determine efforts to reach this population. Home-based testing reaches individuals that were not tested before and who have more risk of acquiring HIV.