Perinatal transmission of hepatitis B virus infection and vaccination in China

Area of Science:

• Hepatology
• Infectious Diseases
• Public Health

Background:

• Hepatitis B virus (HBV) infection is a major public health concern in China.
• Historically high infection and carrier rates, particularly among children, have been documented.
• Despite no significant change in overall rates recently, localized vaccination efforts show positive impacts.

Purpose of the Study:

• To review the epidemiology of Hepatitis B virus (HBV) infection in China.
• To assess the impact of vaccination programs on HBV prevalence.
• To highlight the risks associated with childhood HBV infection and long-term sequelae.

Main Methods:

• Analysis of historical and recent epidemiological data on HBV infection and HBsAg carrier rates in China.
• Review of vaccination strategies and their observed effects on HBsAg positivity in different age groups.
• Examination of transmission routes, including perinatal and horizontal transmission.

Main Results:

• In 1980, HBV infection and HBsAg carrier rates were 42.6% and 10.3% respectively.
• HBsAg positivity in children under 1 year was 5.1-7%, peaking at 24% in 7-14 year olds in Guangdong.
• Areas with universal neonatal HBV vaccination show declining HBsAg positivity in younger demographics.
• Perinatal transmission accounts for 35-50% of carriers, with horizontal transmission also significant.

Conclusions:

• Childhood HBV infection increases the risk of long-term complications like hepatocellular carcinoma (HCC).
• Universal childhood immunization is crucial for controlling HBV infections in China.
• Effective vaccination programs are expected to reduce HBV burden over generations.