Long-term immunogenicity of preservative-free hepatitis B vaccine formulations in adults

摘要

Hepatitis B virus-related diseases are major public health problems with over 2 billion people having been infected with the virus worldwide. In 2004, the World Health Organization (WHO) estimated that there were over 360 million chronic carriers of the virus worldwide. A proportion of these carriers may develop liver cirrhosis and hepatocellu-lar carcinoma later in life in addition to transmitting the virus to others. Estimates indicate that each year, chronic hepatitis B infection causes approximately 600,000 deaths worldwide. Infant vaccination with recombinant hepatitis B vaccines is highly effective in preventing chronic hepatitis B infection in endemic areas. In areas with low hepatitis B endemicity, most hepatitis B infections are acquired in adolescence and adulthood by sexual transmission or intravenous drug use, long after primary vaccination. In such situations, determining long-term persistence of vaccine-induced immunity in adults is crucial. Long-term follow-up studies in adults have shown that hepatitis B vaccine induces persistent anti-hepatitis B surface (anti-HBs) antibody response as well as immune memory against the virus for at least 10 years after primary vaccination.