Xu X, Luo L, Song C, et al. - As HIV antiretroviral therapy (ART) is less effective in presence of pretreatment drug resistance (PDR), researchers aimed to determine PDR prevalence among HIV-positive individuals that initiated antiretroviral therapy in 2014–2020 in southwestern China.

• Blood samples were obtained from 3,236 eligible HIV-positive individuals.

• Analysis revealed a PDR prevalence of 6.0% (194/3,236); indicating overall moderate prevalence of PDR is in Qinzhou.

• There appeared a much higher PDR frequency to non-nucleoside reverse transcriptase inhibitors (3.3%) vs that of nucleoside reverse transcriptase inhibitors (1.7%) and protease inhibitors (1.2%).

• In multivariate logistic regression analysis, significantly higher PDR was noted among individuals aged 18–29 or 30–49, and harboring CRF08_BC.

• Linking a total of 1,429 (43.8%) sequences, transmission clusters were formed ranging in size from 2 to 119 individuals.

• Same drug resistant mutations (DRMs), mostly to non-nucleoside reverse transcriptase inhibitors (50%, 5/10), were observed in 22 individuals in 10 clusters.