Monitoring HIV-1 group M subtypes in Yaoundé, Cameroon reveals broad genetic diversity and a novel CRF02-AG/F2 infection

Broad HIV-1 genetic diversity in Cameroon provides a unique opportunity to monitor HIV-1 evolution and allows the detection of novel strains. We have genetically characterized the HIV-1 subtypes found in 156 samples from 90 drug-naive subjects in Yaoundé, Cameroon collected from 2011 to 2013, using phylogenetic analysis of regions in gag and pol. We identified subtypes CRF02-AG (64.9%), CRF22-01A1 (7.1%), D (4.5%), F2 (3.9%), G (3.2%), CRF18-cpx (3.2%), CRF37-cpx (3.2%), CRF11-cpx (2.6%), CRF13-cpx (1.9%), A1 (1.3%), CRF01-AE (1.3%), CRF09-cpx (1.3%), A2 (0.6%), and H (0.6%). Sequence data for both the gag and pol regions were obtained from 62 subjects; for 59 of these subjects the two regions were identified as the same viral subtype while three subjects were discordant, A1/CRF02-AG (subject MDC006), CRF02-AG/F2 (subject MDC179), and a dual infection with CRF02-AG/F2 (subject MDC131). Longitudinal sequence data were obtained for 28 of these 62 subjects and confirmed the cross-sectional results. These data update subtype information for this area and highlight the necessity of such studies due to the numerous circulating subtypes, the ongoing superinfection, and the risk of emerging novel recombinant viruses.