Dual and recombinant infections: An integral part of the HIV-1 epidemic inBrazil

We systematically evaluated multiple and recombinant infections in an HIV-i nfected population selected for vaccine trials. Seventy-nine HIV-I infected persons in a clinical cohort study in Rio de Janeiro, Brazil, were evaluat ed for 1 year. A combination of molecular screening assays and DNA sequenci ng showed 3 dual infections (3.8%), 6 recombinant infections (7.6%), and 70 (88.6%) infections involving single viral subtypes. In the th ree dual inf ections, we identified HIV-1 subtypes F and B, F and D, and B and D; in con trast, the single and recombinant infections involved only HIV-1 subtypes B and F. The recombinants had five distinct B/F mosaic patterns: Bgag-p17/Bg ag-p24/F-pol/B-env, Fgag-p17/Bgag-p24/F-pol/F-env, Bgag-p17/B-Fgag-p24/F-po l/F-env, Bgag-p17/B-Fgag-p24/F-pol/B-env, and Fgag-p17/B-Fgag-p24/F-pol/F-e nv. No association was found between dual or recombinant infections and dem ographic or clinical variables. These findings indicate that dual and recom binant infections are emerging as an integral part of the HIV/AIDS epidemic in Brazil and emphasize the heterogenous character of epidemics emerging i n countries where multiple viral subtypes coexist.