Immune Responses and Efficacy of Hepatitis B Vaccine in Neonates Born from Hepatitis B Carrier Mothers: Focus on HBV-DNA

ABSTRACT

PURPOSE: The aim of this study was to elucidate the pathogenesis of vertical transmission of hepatitis B virus (HBV), and to study the protective efficacy of the vaccine and hepatitis B immune globulin (HBIG). METHODS: Eighty-two infants born from HBV carrier mothers were studied. HBV plasma-derived vaccine and HBIG were administered to their neonates. Then, changes of viral markers, anti-preS2 and HBV-DNA were observed for 12 months. RESULTS: The seroconversion rates of anti-HBs in infants of HBV carrier mothers at 4, 8 and 12 months were 85.4% (70/82), 75.6% (62/82) and 73.2% (60/82), respectively (P<0.05). The protective efficacy of the vaccine and HBIG at 12 months in infants from HBeAg positive and negative mothers were 89.5% and 100%, respectively. The detection rates of HBV-DNA by PCR in HBeAg positive and negative mothers were 83.3% (15/18) and 23.5% (8/34), respectively. By nested PCR, the detection rates improved to 94.4% (17/18) and 64.7% (22/34), respectively. In neonates from the HBeAg positive and negative mothers, HBV-DNA was only detected by nested PCR with 33.3% (6/18) and 2.9% (1/34), respectively. Five (6.1%) of 82 infants became infected by HBV from only HBeAg positive mothers during the follow-up period of 12 months. Three of 5 infected infants became HBV carriers. Detectable HBV-DNA (P=0.002) and HBsAg (P=0.02) in serum of infants at birth were significant factors to becoming a carrier. CONCLUSION: This study suggests that, in clarifying the HBsAg and HBV-DNA status in serum of the infants at birth, the highest risk group might be identified and treated with new and effective preventive methods.