Characterization of human immunodeficiency virus type 1 from a previously unexplored region of South Africa with a high HIV prevalence.

HIV prevalence in the Limpopo Province has increased rapidly within the past 10 years, as in other parts of South Africa. Little is known about the genetic and biological properties of HIV circulating in this region including the baseline drug resistance profiles. We therefore collected blood samples from 42 HIV-1-infected patients residing in this region for analysis. All samples were shown to belong to HIV-1 subtype C by env and gag heteroduplex mobility assay (HMA). Viral isolates from 14 of these patients were shown to use the CCR5 coreceptor exclusively and had gp120 V3 loop sequences consistent with this phenotype. Sequence analysis of both protease and reverse transcriptase genes showed that none of 13 isolates harbored primary resistance mutations. These data suggest that HIV-1 subtype C is the predominant subtype circulating in the Limpopo Province, and that viral strains from this region are indistinguishable from those found in other parts of South Africa.