Real-world efficacy of immunoprophylaxis against mother-to-infant transmission of hepatitis B virus based on puerperant population

Abstract

Objective To assess the efficacy of immunoprophylaxis against mother-to-infant transmission of hepatitis B virus (HBV) in a real-world setting since the implementation of charge-free hepatitis B immunoglobulin (HBIG) and hepatitis B vaccine in China. Methods The screening rate and the prevalence of hepatitis B surface antigen (HBsAg) in 61 790 puerperants, and the administration of combined immunoprophylaxis in infants of HBsAg-positive mothers in Rugao City of Jiangsu Province from July 1, 2011 to June 30, 2016 were retrospectively analyzed. HBV infection status of infants born to HBV infected mothers was followed up after 7 months of age. HBsAg-positive infants and their mothers were followed up again for HBV markers in April 2018. Fisher's exact test and Cochran-Armitage trend test were used to statistically analyze the differences between groups and various years, respectively. Results All 61 790 puerperants were screened for HBsAg and the prenatal screen rate was 98.6% (60 937/61 790) with an increasing trend over time (χ2trend=750.908, P<0.001). HBsAg-positive puerperants accounted for 5.5% (3 397/61 790) with a decreasing trend over time (χ2trend=32.667, P<0.001). In total, 778 offspring (399 boys and 379 girls) of 759 HBsAg-positive mothers were followed up at (13.7±6.9) months of age, among which 751 (96.5%) were administered and 25 (3.2%) were probably administered standard combined immunoprophylaxis after birth, and the rest two (0.3%) were not. Fourteen infants (1.8%) were HBsAg positive and all born to mothers with positive hepatitis B e antigen (HBeAg). None of the 538 infants born to HBeAg-negative mothers was HBsAg-positive. HBsAg-positive rate in infants born since 2013 was lower than those in 2011 and 2012 (χ2trend=13.352, P=0.000 3). Eleven HBsAg-positive mothers and their children were followed up again 4–5 years later in April 2018. HBV DNA levels of all mothers were within the range of (7.34–28.2)×107 IU/ml except one case of spontaneous HBeAg seroconversion. One out of the 11 infected children also had HBeAg seroconversion. Phylogenetic analysis of HBV S gene showed that the 11 pairs of mothers and children were all infected with HBV of genotype C. Conclusions The implementation of charge-free HBIG and hepatitis B vaccine for newborns achieves fruitful results in Rugao city as the mother-to-infant transmission of HBV in the real-world had been further reduced to a similar level reported in literature survey. Key words: Hepatitis B virus; Hepatitis B; Infectious disease transmission, vertical; Immunoglobulins; Communicable disease control