Prevalence of primary drug resistance-associated mutations among HIV type 1 vertically Infected children in Belo Horizonte, Brazil.

In the past few years there has been increasing concern about the transmission of drug-resistant HIV. This study aimed to describe the frequency of primary mutations associated with HIV-1 drug resistance and the prevalence of genetic HIV subtypes in a population of vertically infected children before the initiation of HAART. At the time of genotypic testing, the median age was 6.0 years (IQR 25-75%: 3.8-9.2) and the median age at admission was 3.84 years (IQR 25-75%: 1.23-6.11). Antepartum maternal ARV exposure for PMTCT occurred for three (7.3%) mothers. According to the WHO criteria, primary ARV resistance mutations were detected in four out of 41 (9.8%) children. Subtype B was the most prevalent (63.4%). The relatively high prevalence of primary HIV-1 DRMs in this cohort of perinatally infected children in Brazil supports the local recommendation to perform resistance testing in all newly diagnosed children, regardless of age at diagnosis and antenatal ARV exposure.