High acceptability of rapid HIV test in Argentina. Experience during a seroprevalence study in vulnerable groups.

DURAN A; ROSSI D; MARONE R; ORELLANO G; ROMERO M; PETRACCA C; BENEDETTI E; AVILA MM; SALOMON H; PANDO MA

Vancuver

Conferencia; 8th IAS Conference on HIV Pathogenesis, Treatment and Prevention; 2015

IAS

Background: The Ministryof Health in Argentina recently updated the HIV diagnosis algorithm,incorporating the rapid HIV test (RHT) and the confirmation of reactive caseswith HIV viral load instead of Western blot. Thisnew algorithm was implemented for the first time in Argentina to evaluate acceptabilityand accuracy of the RHT in a seroprevalence HIV study among vulnerable groups fromBuenos Aires Metropolitan Area.  Methods: FromSeptember 2013 to May 2014, a cross-sectional HIV seroprevalence survey wasconducted at different settings (non-governmental organizations, hospitals andfield visits). Men who have sex with men (MSM), female transgender/travesties,drug users (DU) and female sex workers (FSW) were included in the study. HIVdiagnosis was performed with Allere Determine HIV-1/2. All samples were alsotested with Genscreen Ultra HIV Ag&Ab. Reactive cases were confirmed withviral load (bDNA Versant HIV RNA). CD4 cell count was also performed.  Results: Between September 2013 and May 2014, 1517 individuals were tested. RegardingRHT acceptability, 99.5% of participants reported that proceedings had been"good" or "very good" and 91.2% preferred to know resultsin the same day. For 19% of the participants this was the first time theytested for HIV. Prevalence of HIV infection was 11.5% (116/1015, 95% CI 9.5-13.5)for MSM, 31.5% (52/165, 95% CI 24.1-38.9) for female transgender/travesties, 3.5%(9/259, 95% CI 1.1-5.9) for DU and 5.1% (4/78, 95% CI 1.4-12.6) for FSW. Comparisonof RHT with standard laboratory diagnosis showed 10 discordant results (0.66%).RHT sensitivity and specificity was 97.3% and 99.6%, respectively (PPV: 96.7%,NPV: 99.7%). Acute HIV infection was detected in the laboratory in four MSMwith a negative RHT. Fifty eight percent of HIV positive individuals had lessthan 500 CD4/µl at diagnosis.  Conclusions: Implementation of RHT was successful, revealing that its implementationcould be a useful tool to facilitate access to diagnosis in vulnerable groups,where prevalence of HIV remains extremely high. RHT expansion, improving earlydiagnosis, would diminish the frequency of individuals that are diagnosed at advancedstages of the infection.