Abstract
WHAT IS ALREADY KNOWN ABOUT THIS TOPIC? Post-vaccination serologic testing (PVST) of infants born to hepatitis B virus (HBV) infected mothers is important for evaluating effectiveness of strategies for preventing mother-to-child transmission (MTCT) of HBV. WHAT IS ADDED BY THIS REPORT? PVST was conducted in 43.7% of 7,425 infants born to HBV-infected mothers and showed that 0.8% of infants had breakthrough infections, indicating a very low level of prevention failure; anti-HBs positivity was 97.0% showing vaccine-induced protection; and 2.2% of HBV-exposed infants needed revaccination. Prevention failure was 12.7-fold higher among infants born to HBeAg-positive mothers. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE? MTCT prevention strategy is highly effective. PVST evaluates MTCT prevention strategy and identifies infants needing revaccination; its use should be increased. Findings support WHO's HBV elimination strategy.