According to a report published in the Annals of Internal Medicine, three doses of hepatitis B vaccines are adequate to protect against the infection for at least 15 years. The previous reports have shown that hepatitis B vaccine provides protection for 10 years only. However the follow-up period of this study was 15 years and the hepatitis protection beyond this period was unclear.
The study investigators analyzed data from 1578 Alaska natives who were vaccinated at 6 months of age and older. In 1981- 82, the study subjects received three doses of plasma-derived hepatitis B vaccine. The main predictor of virus protection was antibody to hepatitis B surface antigen (anti-HBs). The Mean levels of antibody to hepatitis B surface antigen (anti-HBs) were 822 mIU/mL after vaccination and fell to 27 mIU/mL after 15 years.
The researchers found that the vaccination between 6 months and 4 years was associated with low anti-HBs levels at follow-up. Whereas predictors of higher anti-HBs levels at 15-year follow-up included high initial levels, older age at vaccination and male gender.
The research team concluded that hepatitis B vaccination strongly protected against infection for at least 15 years in all age group. This conclusion argue against a need for booster vaccinations for hepatitis B. This study further indicated that unless continued follow-up and surveillance show clinically significant rates of infection in adolescents or adults who were vaccinated as children, booster vaccinations will be wasteful.