Option A improved HIV-free infant survival and mother to child HIV transmission at 9-18 months in Zimbabwe.

Objective: We evaluated the impact of Option A on HIV-free infant survival and mother-to-child transmission (MTCT) in Zimbabwe.

Design: Serial cross-sectional community-based serosurveys.

Methods: We analyzed serosurvey data collected in 2012 and 2014 among mother-infant pairs from catchment areas of 132 health facilities from five of 10 provinces in Zimbabwe. Eligible infants (alive or deceased) were born 9-18 months before each survey to mothers at least 16 years old. We randomly selected mother-infant pairs and conducted questionnaires, verbal autopsies, and collected blood samples. We estimated the HIV-free infant survival and MTCT rate within each catchment area and compared the 2012 and 2014 estimates using a paired t test and number of HIV infections averted because of the intervention.

Results: We analyzed 7249 mother-infant pairs with viable maternal specimens collected in 2012 and 8551 in 2014. The mean difference in the catchment area level MTCT between 2014 and 2012 was -5.2 percentage points (95% confidence interval = -8.1, -2.3, P < 0.001). The mean difference in the catchment area level HIV-free survival was 5.5 percentage points (95% confidence interval = 2.6, 8.5, P < 0.001). Between 2012 and 2014, 1779 infant infections were averted compared with the pre-Option A regimen. The association between HIV-free infant survival and duration of Option A implementation was NS at the multivariate level (P = 0.093).

Conclusion: We found a substantial and statistically significant increase in HIV-free survival and decrease in MTCT among infants aged 9-18 months following Option A rollout in Zimbabwe. This is the only evaluation of Option A and shows the effectiveness of Option A and Zimbabwe's remarkable progress toward eMTCT.