Long-term persistence of anti-HBs after hepatitis B vaccination among adults: 8-year results.

The long-term persistence of hepatitis B surface antibody (anti-HBs) after hepatitis B vaccination among adults was not known clearly. This study aimed to assess the immunogenicity and persistence of antibodies 8 years after hepatitis B immunization with different vaccination schedules among adults who tested negative for hepatitis B surface antigen (HBsAg), anti-HBs, and hepatitis B core antibody (anti-HBc). A total of 771 participants who received the full vaccination course (three doses) and also had a blood sample taken 1 month after the first vaccination were recruited. Of these, 529 were excluded due to the missing data of anti-HBs 8 years after the first vaccination. Vaccinations were carried out at 0-1-3, 0-1-6 and 0-1-12 month vaccination schedules, and 104, 45, and 93 participants were included, respectively. The positive seroprotection rate was 85.9% 1 month after the third vaccination, and 58.3% 8 years later (χ2 = 54.52, P < .001), while the geometric mean titer (GMT) of anti-HBs was 158.49 mIU/mL [95% confidence interval (CI): 131.83-190.55)] and 15.14 mIU/mL (95% CI: 10.96-20.42) after 1 month and 8 years, respectively. Compared with the standard 0-1-6 month vaccination schedule, the positive seroprotection rate and the GMT of the 0-1-3 month vaccination schedule had no difference. The long-term immune effect of the 0-1-3 month vaccination schedule was better than that of the 0-1-12 month vaccination schedule. No correlation was found between the GMT of anti-HBs 1 month and 8 years later.