Rate of Acquired Immunity in Dental Students after Hepatitis B Vaccination

BACKGROUND Triple-course vaccination against hepatitis B might sometimes fail to increase antibody titers or maintain it at sufficient levels. The aim of this study was to evaluate the rate of seroprotection in dental students after receiving recombinant hepatitis B vaccine. METHODS Anti-HBs levels of 124 dental students who had received triple-course hepatitis B vaccines (scheduled at months 0, 1, and 6) were examined. Titers ≥ 100 mIU/ml were considered as protective. Associations between age, gender and duration of being vaccinated with the titer of anti-HBs were assessed. RESULTS The participants' mean age was 24 ± 1.3 years and 93% of them were female. The time passed from receiving the final dose was 3.5 ± 1.4 years. Fifty four percent of the students had protective immune response (95% CI 45.2% to 62.8%), 24.2% had positive but weak immune response (anti-HBs titer was between 10 and 100 mIU/ml), and the rest of the subjects (21.8%) were seronegative after receiving routine HBV vaccination. CONCLUSION There was a considerable rate of failure in achieving or maintaining acceptable titer levels following routine vaccination against HBV. Hence, determining serum anti-HBs titer after vaccination is recommended.