PMTCT and early infant diagnosis among HIV-exposed infants in Gabon: associations with HIV infection and continuity of care

Despite major progress in the prevention of mother-to-child transmission (PMTCT) of HIV, pediatric HIV infection remains a significant public health challenge in sub-Saharan Africa. In Gabon, data on early infant diagnosis (EID) and postnatal follow-up of HIV-exposed children are scarce. This study assessed the association between maternal receipt of PMTCT and infant HIV infection and identified factors associated with gaps in EID and pediatric HIV care. We conducted a observational study between August 2021 and January 2024 among 713 HIV-exposed children and 713 their biological mothers in Gabon. Data were collected using a structured questionnaire and supplemented with HIV DNA PCR results. Maternal PMTCT receipt was defined as receipt of antiretroviral therapy or prophylaxis during pregnancy and/or breastfeeding. Sociodemographic characteristics, follow-up indicators, and virological outcomes were analyzed. Bias-reduced multivariable logistic regression models were used to identify factors independently associated with infant HIV infection and EID completion. A total of 713 mother-child pairs were included, with one child per mother. PMTCT coverage was 91.9% (655/713), and HIV infection prevalence among exposed children was 5.2% (37/713). Among children whose mothers did not receive PMTCT, 22/58 (37.9%) were HIV-positive, compared with 15/655 (2.3%) among those whose mothers received PMTCT. In multivariable analysis, maternal receipt of PMTCT was associated with lower odds of infant HIV infection (OR = 0.04; 95% CI: 0.02–0.08; p < 0.001). The mean number of PCR tests per child was 1.6 ± 0.9, and only 12.5% (89/713) completed EID. Specialized pediatric HIV care was documented for 41.4% (295/713) of children. Follow-up in specialized pediatric HIV care was not independently associated with infant HIV infection (OR = 1.00; 95% CI: 0.46–2.13; p = 0.995) or EID completion (OR = 1.16; 95% CI: 0.01-222.85; p = 0.943). Maternal receipt of PMTCT was strongly associated with lower odds of HIV infection among HIV-exposed children, although residual infections persisted. EID completion remained low, highlighting important gaps in the pediatric HIV care cascade. Strengthening postnatal follow-up, systematic tracking of HIV-exposed infants, repeated virological testing, and access to specialized pediatric HIV services should be prioritized to improve pediatric HIV care in Gabon.