Protective efficacy against chronic hepatitis B virus infection after neonatal hepatitis B vaccination in China: A summary

Abstract

Transmission of hepatitis B virus (HBV) during the perinatal period and in young children has been effectively prevented in recent years, with increased rates of coverage and timely immunization of hepatitis B vaccine to neonates in mainland China. Prevalence of HBV surface antigen (HBsAg) and chronic HBV infection in children have decreased both in rural and urban areas. The incidence of hepatitis B and primary hepatocellular carcinoma has also been reduced in children and young people. The effects of immunoprotection against HBV infection were found to last for at least 20 years. The presence of immune memory was associated with titers of antibody to HBV surface antigen (anti-HBs) in young children vaccinated at an early age. Results from our recent clinical investigation suggest that a universal booster immunization is not necessary for children and teenagers after neonatal vaccination. In this review, issues arising from representative vaccination-coverage areas, including Qidong, Jiangsu Province, are also discussed. These include immunoprophylaxis failure against vertical transmission, low or no response to the vaccines, isolated anti-HBc positivity, occult HBV infection after vaccination, and the effects of vaccination on HBV genotype and mutation.