HIV type 1 molecular epidemiology in pol and gp41 genes among naive patients from Mato Grosso do Sul State, central western Brazil.

Antiretroviral naive patients (n=49) were recruited in central western Brazil (Campo Grande City/Mato Grosso do Sul State, located across the Bolivia and Paraguay borders). HIV-1 protease (PR), reverse transcriptase (RT), and env gp41 HR1 fragments were sequenced. Genetic diversity was analyzed by REGA/phylogenetic analyses. Intersubtype recombinants were identified by SimPlot/phylogenetic trees. PR/RT resistance was analyzed by Calibrated Population Resistance/Stanford databases. T-20 resistance in gp41 was assessed by Stanford, Los Alamos, and other sources. Of HIV-1 subtypes 65.3% were B(PR)B(RT), 10.2% were C(PR)C(RT), and 8.2% were F1(PR)F1(RT). Intersubtype recombinants were 16.3%: four B/F1 and four B/C (two were "CRF31_BC-like"). The Pol-RT V75M mutation was detected in two homosexual partners; one patient had the T215S revertant mutation. T-20/gp41 resistance mutations were L44M (n=2) and V38A (n=1). The high percentage of non-B isolates (∼35%) highlights the importance of molecular surveillance studies in settings distant from the origin of the epidemic. Our data help elaborate the molecular epidemiological map of HIV-1 in Brazil.