Impact of the implementation of a vaccination strategy on hepatitis B virus infections in China over a 20-year period

Abstract

Hepatitis B virus (HBV) vaccination has been recommended for all neonates in China since 1992. This article reviews the impact of HBV vaccination throughout the past 20 years in China. Before the introduction of the HBV vaccination program, approximately 9.8% of the general Chinese population tested positive for hepatitis B virus surface antigen (HBsAg). Since 1992, vaccination coverage has increased each year. In 1999, a National Expanded Programme on Immunization (EPI) review showed that the immunization coverage with three doses of HBV vaccine was 70.7%, and reached 99.0% in Beijing. The HBsAg carrier rate in the general population decreased to 7.2% in 2006. In particular, the prevalence of HBsAg decreased to 2.3% among children aged 5-14 years and to 1.0% among children younger than 5 years. In addition, the administration of the HBV vaccine may have reduced the risk of hepatocellular carcinoma among adults. Despite the administration of hepatitis B immunoglobulin and the HBV vaccine to children with HBsAg-positive mothers, the failure rate of HBV immunoprophylaxis was 5-10%. In China, vaccine failure was related to HBV S gene mutation and inadequate administration of HBV vaccine. The prevalence of HBV carriers in China was markedly reduced after the introduction of the universal HBV vaccination program. If we immunize all susceptible individuals with the hepatitis B vaccine (especially children), interrupt transmission, and provide antiviral treatment for existing HBV carriers, the number of new cases may be reduced to close to zero in the future and this may eventually result in the eradication of HBV.

Serological and molecular epidemiological outcomes after two decades of universal infant hepatitis B virus (HBV) vaccination in Nunavut, Canada

“…The anti-HBs prevalence increase from individuals aged <1 to 1 year old could be due to the infants <1 years old not receiving all 3 doses of vaccination, leading to a potential decrease in individuals with protective antibody level. Incomplete vaccination has been highly associated with becoming an HBV carrier upon exposure to HBV, opposed to those fully vaccinated [114]. However, the rate of decay after primary and secondary doses in infancy has not been studied, and therefore the lowered protective anti-HBs level in infants <1 years old may or may not be attributable to lack of full vaccination.…”

Seroprevalence of hepatitis B surface antigen and hepatitis B e antigen among childbearing-age women in Mianyang, China

“…However, the prevalence of HBV infection still remains as high as 7.18% [3]. Special protective strategies for childbearing-age women are lacking, with the exception of premarital medical examination for HBV [22].…”

“…There are still more than 350 million chronic HBV infection carriers worldwide, who face a lethal risk of developing hepatic decompensation, cirrhosis, and hepatocellular carcinoma (HCC) [2]. In China, the improvements in socioeconomic status and hygienic conditions, the introduction of general vaccination, as well as complete sterilization of medical instruments, have led to a decline in the prevalence of HBV infection [3]. However, it still remains as high as 7.18%, and 300,000 people die from HBV-related diseases annually, accounting for 40%-50% of HBV-related deaths worldwide [1,3].…”

“…In China, the improvements in socioeconomic status and hygienic conditions, the introduction of general vaccination, as well as complete sterilization of medical instruments, have led to a decline in the prevalence of HBV infection [3]. However, it still remains as high as 7.18%, and 300,000 people die from HBV-related diseases annually, accounting for 40%-50% of HBV-related deaths worldwide [1,3]. It was estimated that even for residents with health insurance, the direct cost caused by HBV infection exceeded 40% of resident's disposable household income in China [4].…”

“…For these newborns, postexposure prophylaxis with hepatitis B vaccine and hepatitis B immune globulin (HBIG) within 24 hours of birth have been recommended to tremendously reduce the prevalence of HBV infection [3]. However, the incidence of immunoprophylaxis failure still remains [11].…”