Impact of the National Prevention of Mother to Child Transmission of HIV (PMTCT) Program on Perinatal Mother-to-Child Transmission of HIV (MTCT) Measured at 6 weeks Postpartum, South Africa (SA): Results of the First Year of Implementation of the 2010 PMTCT Guidelines Recommended by the World Health Organization (WHO)

Background: Effectiveness of implementing the 2010 WHO PMTCT recommendations has not been assessed at population level. SA began implementation of the WHO PMTCT Option-A recommendation in April 2010. We assessed the impact of the first year of implementation of Option-A on perinatal MTCT measured at 4-8wks postpartum. Methods: We conducted a nationally representative, cross-sectional facility-based survey of infant-caregiver pairs attending the first immunization visit using a stratified multi-stage sampling design. Data were collected through caregiver interviews and/or from Road-to-Health cards between August 2011 and February 2012. HIV-exposed infants (HEI) were identified if their dried-blood-spot (DBS) specimens collected at 4-8wks were HIV-antibody positive. DBS specimens of HEI were then tested for HIV infection using DNA-PCR. Results: Of 9793 enrolled caregiver-infant pairs, 2914 (29.8%) HEI were identified. Of 2454 HEI whose mothers knew their own infection status, triple-antiretrovirals were provided to 1075 (43.8%) mothers of whom 72% with CD4 counts ≤350 cell/µl and 25.5% with CD4 counts >350 cell/µl. The unweighted national MTCT rate measured at 4-8wks postpartum was 3.0%. Controlling for maternal CD4, odds of MTCT were higher in mother-HEI pairs receiving ≤10wks of maternal-AZT and infant-NVP at birth compared with those receiving >10wks of the same regimen (AOR=2.4; 95%CI 1.1-5.5). Conclusion: After one year implementing the 2010 WHO Option-A PMTCT recommendations, SA has decreased MTCT measured at 4-8wks postpartum to 3%. Data suggest that early antiretroviral initiation is likely to increase effectiveness. Overall MTCT and survival rates around 18-months are needed to estimate the effectiveness of extended NVP-prophylaxis during breastfeeding.