There is still no suitable routine hepatitis B immunization strategy for adults in China. To establish an optimal vaccination schedule for healthy adults, we investigated various schedules in healthy adults. In this randomized 5143 healthy adults received 10 μg hepatitis B vaccine at 0, 1 and 3 months(group A), 0, 1 and 6 months(group B), or 0, 1 and 12 months(group C). Blood samples were collected after 1 month and 12 months after the third dose. The geometric mean titer (GMT), seroconversion rate (levels of anti-HBs ≥ 10 mIU/mL) and high response rate (levels of anti-HBs ≥ 100 mIU/mL) were assayed. In our study, 2438 healthy adults finished the full vaccination program and follow-up. The seroconversion/sero-protective rate of groups A-C at one and 12 month after administration of the third vaccine dose was 100%, 99.9% and 97.9% verse 64.9%, 75.7% and 79.0%, respectively. GMT for anti-HBs tested in group A to C within 1 or 12 month after the third vaccination was 213.16, 432.58 and 451.47 mIU/ml verse 22.07, 46.70 and 56.18 mIU/ml, respectively. There were significant differences of seroconversion/sero-protective rate and GMT among the 3 groups (p < 0.01). Given the high anti-HBs seroconversion rate and GMT in all 3 groups, a flexible schedule for Hepatitis B vaccine should be recommended to adults, but 0-1-12 schedule is a better choice.
Keywords: adult vaccination; anti-HBs titers; hepatitis B vaccine; immunogenicity.