Dinh TH, et al. - This study sought to report the 18-month mother-to-child human immunodeficiency virus (HIV) transmission (MTCT) risk during the transition from Option A to B-plus in Zimbabwe, and assess whether antiretroviral treatment (ART) pre-conception could eliminate MTCT in breastfeeding populations. Findings revealed ART pre-conception as most impactful regarding reducing MTCT, indicating that HIV-infected, reproductive-age women should be prioritized in “treat-all” strategies. Researchers suggested identifying HIV-infected mothers without ART at the first immunization visit and initiating treatment to reduce post-delivery MTCT. Higher MTCT risk was identified in mothers with LBW deliveries.

Methods

• In 2013, consecutive recruitment was performed of a nationally representative sample of 6,051 infants aged 4-12 weeks and their mothers from 151 immunization clinics using a multistage stratified cluster sampling method.
• 1,172 HIV-exposed infants (HEIs) were identified; these were evaluated at baseline and every three months until the child became HIV-infected, died, or reached age 18 months.

Results

• Through 18 months post-delivery, the cumulative MTCT risk was 7.0%.
• Of the HIV-infected mothers, ART was initiated pre-conception in 35.3%, during pregnancy in 28.9% , after delivery in 9.7%, and 16.0% received zidovudine during pregnancy.
• Compared to mothers without antiretroviral drug use, MTCT among those starting ART pre-conception and during pregnancy seemed lower by 88% (adjusted hazard ratio [HR] 0.12; 95% confidence interval [0.060.24]) and 75% (adjusted HR 0.25; 0.140.45), respectively.
• Findings revealed that HEIs with birth-weight <2.5kg (LBW) were 2.6-fold more likely to acquire HIV infection compared to those with birth-weight ≥2.5kg (adjusted-HR 2.57; 1.444.59).
• Controlling for other factors, breastfeeding indicated no significant association with MTCT.