Primary resistance of human immunodeficiency virus type 1 in a reference center in Recife, Pernambuco, Brazil

To assess the prevalence of primary resistance of human immunodeficiency virus type 1 (HIV-1) to antiretrovirals, 84 patients chronically infected with HIV without prior antiretroviral treatment from Northeast Brazil were studied. Genotyping was performed using the ViroSeqTM Genotyping System. Thimidine analog mutations occurred in 3 (3.6 percent) patients. Accessory mutations related to NRTI occurred in 6 (7.1 percent) and related to PI in 67 (79.8 percent). Subtypes B (72.6 percent), F (22.6 percent), B/F 3 (3.6 percent), and C (1.2 percent) were detected. A low prevalence of major mutations related to NRTI in patients chronically infected by HIV was observed.