The inception, achievements, and implications of the China GAVI alliance project on hepatitis B immunization. (Special Issue: Hepatitis B and the impact of immunization in China and the WHO Western Pacific Region.)

摘要

The China GAVI Hepatitis B Immunization Project was initiated in 2002 with the signing of a Memorandum of Understanding between GAVI and the Government of China. It was designed by the Chinese Government and partners to deliver free hepatitis B vaccine and safe injections to all newborns in the 12 Western Provinces and Poverty Counties in 10 Provinces of Central China, eliminating the gap in immunization coverage between wealthier and poorer regions of China. The project budget (USD 76 million) was equally shared by GAVI and the Chinese Government. Initially planned for 5 years, two no cost extensions extended the project to 2011. Although China produced hepatitis B vaccine before the project the vaccine was sold to parents who were also charged a "user fee" for the syringe and vaccine administration. Basic Expanded Program on Immunization (EPI) vaccines such as BCG, DTP, Polio, and measles vaccines were provided free to parents, although they were charged a user fee. The result of charging for hepatitis B vaccine was that coverage was relatively high in Eastern and wealthier counties in Central China (~80-90%), but was much lower (~40%) in Western China and Poverty Counties where parents could not afford the vaccine. The initial targets of the project as delineated in the initial MOU for the Project areas (HepB3 coverage will reach 85% at the county level, >75% of newborns at the county level will receive the first dose of hepatitis B within 24 h of birth, and all immunization injections will be with auto disable [AD] syringes) were substantially exceeded. The differential in vaccine coverage between wealthier and poorer parts of China was eliminated contributing to a great improvement in equity. With additional contributions of the Chinese Government, the Project was accomplished substantially under budget allowing for additional catch up immunization of children under 15 years of age. More than 5 million health workers were trained in how to deliver hepatitis B vaccine, timely birth dose (TBD), and safe injections, and public awareness of hepatitis B and its prevention rose significantly. TBD coverage was expedited by concurrent efforts to have women deliver in township clinics and district hospitals instead of at home. The effective management of the Project, with a Project office sitting within the China EPI and an Operational Advisory Group for oversight, could serve as a model for other GAVI projects worldwide. Most importantly, the carrier rate in Chinese children less than 5 years of age has fallen to 1%, from a level of 10% before the inception of the Project. Liver cancer, one of the major cancer killers in China (250,000-300,000 annual estimated deaths), will dramatically decline as immunized cohorts of Chinese children age. While hepatitis C and non-alcoholic liver disease also exist in China and can lead to liver cancer and cirrhosis, the majority of liver disease in China is hepatitis B related and therefore preventable. The authors believe that China's success in preventing hepatitis B is one of the greatest public health achievements of the 21st century. Work remains to be done in several key areas. There are still pockets of home births in rural provinces where a TBD is difficult to deliver, and China is strengthening its policy of screening pregnant women for HBsAg and delivering HBIG plus vaccine to newborns of HBV carrier mothers. Approximately 10% of the adult population of China remain chronic carriers of hepatitis B virus and cannot be helped by the vaccine, so prevention of liver cancer and cirrhosis in those groups remains a future challenge for China.