Prevalence and Incidence of HIV, HBV and HCV among at-risk groups in Argentina.

AVILA MM; PANDO MA; MARTINEZ PERALTA L; MAULEN S; ROSSI D; DE SALVO C; REY J; BENETUCCI J; CASCO R; LOSSO M; CASIRO A; CAHN P; MONTANO S; SANCHEZ J; WEISSENBACHER M

New York

Conferencia; AIDS Vaccine 2003; 2003

Background: The epidemic in Argentina has changed throughout the years. It was almost limited to Men who have Sex with Men (MSM) in the ‘80s, changed to Injecting Drug Users (IDUs) in the ‘90s and to mainly heterosexual in 2000. The CNRS, in collaboration with Hospitals and NGOs from Buenos Aires City, compiled a number of HIV seroprevalence and seroincidence studies in vulnerable populations as basis for planning vaccine clinical trials in the near future. Methods: Prospective seroprevalence studies for HIV in vulnerable populations in Buenos Aires and other cities from Argentina were carried out as from 2000 through 2003. Six populations were studies: MSM, Female Sex Workers (FSW), IDUs, Cocaine Non Injecting Drug Users (Non-IDUs), patients with diagnosis of tuberculosis (TBC) and patients who assist to sexual transmitted diseases clinics (STDs). Seroincidence studies for HIV were performed in MSM (by a follow up study and by detune assay) and IDUs (by detune assay). Seroprevalence for hepatitis B and C was also performed. HIV subtyping by Heteroduplex Mobility Assay (HMA) were done in HIV positive samples. Sequencing were performed in some selected samples. Results: The table described the HIV, HBV and HCV seroprevalence, HIV seroincidence and HIV subtype in the different populations.   HIV+/Total HIV Prev.      (%)           HIV Incidence        (% p/y)          HIV Subtype     HBV Prev. (%)    HCV Prev. (%) MSM     96/694     13.8        4.8 89.5% B  10.5% F (HMA)       34       1.6 FSW     20/625      3.2       ND     36%B   64%F (HMA)       15       4.4 IDUs     77/174     44.3        0.0       100%  B/F  (seq)      42.5      54.6 Non-IDUs     32/504      6.3       ND                    ND       8.9       7.5 TBC     35/211     16.6       ND     25%B  75%F (HMA)       ND       ND STDs     59/801     7.4       ND                    ND       ND       ND Conclusions: Different HIV prevalence were detected in the selected populations. Very high among IDUs, though no new infections were detected by detune assay. On the contrary, MSM showed a lower prevalence but a high incidence (near 5%). Subtypes B and F were detected by HMA in MSM, FSW and TBC patients with different rates. Sequenced samples from IDUs detected B/F recombinants in all of them.