Study on the blocking effect of injecting HBsAg positive mothers during pregnancy and their infants at birth with HB immunoglobulin on mother-to-infant transmission of HBV

Objective To study the effect of HB immunoglobulin (HBIG) on HBsAg positive mothers during the third trimester of pregnancy and combined use of HBIG and HB vaccine to infants on the blocking of vertical transmission of HBV and the status of hepatitis B resulting from mother-to-infant transmission. Methods A total of 645 HBsAg positive mothers were divided into two groups, group 1 without HBIG and their infants with three doses of plasma-derived vaccine given at 0, 1 and 6 months; group 2 with HBIG200IU respectively during the third trimester of pregnancy and their infants with HBIG200IU at birth and three 5 μg doses of recombinant vaccine given at 0, 1 and 6 months. All infants were followed up for the hepatitis B detection at the age of 1, 3, 6, 12, 24 months by enzyme-linked immunoadsorbent assay (ELISA). Results 9 infants which were infected chronically with HBV were all in group 1, among them 8 were HBsAg positive before the age of 6 months mainly attributing to intrauterine infection. No infants were infected chronically by HBV in group 2. The chronical infection rate of HBV of infants in group 1 was significantly higher than that in group 2, ( χ 2=4.008, P0.05). Conclusions Use of HB immunoglobulin (HBIG) to HBsAg positive mothers during the third trimester of pregnancy and combined use of HBIG and HB vaccine to infants could block the chronicity of HB resulting from intrauterine infection.