By 2011, South African prevention of mother-to-child transmission of HIV (PMTCT) programmes had reduced perinatal HIV transmission at 6-weeks of age to 2.7%. We investigated the profile of newly-diagnosed vertically-infected children and their mothers to identify short-falls in the PMTCT programme.

In this operational follow-up study, fieldworkers enrolled mothers of newly-diagnosed HIV-infected children up to 2 years of age at 5 major healthcare facilities in Johannesburg. Structured questionnaires and clinical record reviews were conducted and analysed to describe the population and assess factors associated with PMTCT uptake.

289 mother-child pairs were enrolled. Timing of maternal HIV diagnosis influenced PMTCT access and feeding choices, and was associated with infants’ age at HIV diagnosis (7 weeks vs. 11 weeks vs. 31 weeks where mothers tested before, during or after the pregnancy respectively; p <0.0001). Women diagnosed before pregnancy (12%) were older (median 31 years) than those diagnosed during the index pregnancy (53% - median 27 years). Women diagnosed after delivery (35%) were younger (median 25 years, p<0.0001), of lower parity, and less likely to be South African citizens. In 81 cases (29%) late maternal diagnosis precluded any PMTCT access. Where women were diagnosed during or before pregnancy, the recommended PMTCT guidelines for mother and infant were followed in 86 (61%) pairs.

Failure to diagnose maternal HIV infection before delivery was the main reason for missing PMTCT prophylaxis and early infant testing. Timely maternal diagnosis enables PMTCT uptake, but implementation and follow-up gaps require attention to improve infant outcomes.