Journal of medical virology 2016 4 1() doi 10.1002/jmv.24540
Primary infection, seroconversion and transmitted drug resistance (TDR) during pregnancy may influence the risk of mother-to-child-transmission (MTCT) of HIV-1 infection. This study estimated recent seroconversion, TDR rates, HIV-1 subtypes and pregnancy outcomes among 95 recently diagnosed, antiretroviral (ARV)-naïve pregnant women recruited during antenatal care in central western Brazil. Recent seroconversion was defined by BED-capture enzyme immunoassay (<155 days) and ambiguous nucleotides base calls (<1 year) in pol sequences (protease-PR and reverse transcriptase-RT regions). TDR was evaluated by the Calibrated Population Resistance tool. HIV-1 subtypes were defined by REGA and phylogenetic analyses. The median age of participants was 25 years; the median gestational age at diagnosis was 20.5 weeks. Based on serology and sequence polymorphism, recent infection was identified in 11.6% (11/95) and, 9 of them (82%), probably seroconverted during pregnancy; one MTCT case was observed among them. Three cases of stillbirth were observed among chronic infected patients (3.6%; 3/84). Moderate rate of TDR was observed (9/90, 10% CI-95% 4.7-18.1%). Subtype B was 60% (54/90), 13.3% (12/90) was subtype C, 6.7% (6/90) was subtype F1. Recombinant B(PR) /F1(RT) and F1(PR) /B(RT) viruses comprised 15.5% (14/90); B(PR) /C(RT) mosaics represented 4.4% (4/90). Seroconversion during pregnancy, late presentation to antenatal care and moderate TDR identified in this study represent significant challenges for the MTCT elimination. This article is protected by copyright. All rights reserved.