Effects of Hepatitis B Revaccination in Nonresponsive Children

ABSTRACT

PURPOSE: Hepatitis B virus infection is prevalent in Korea. Active immunization of Hepatitis B has been proceeded extensively for the last decade. This study was performed to estimate the negative rate of anti-HBs after immunization and to evaluate the effect of revaccination among Korean children between 1995 and 1997, as well as to determine a proper revaccination schedule. METHODS: Anti-HBs was measured with enzyme immunoassay. Hepatitis B revaccination was performed on nonresponders, those who were previously vaccinated and whose anti-HBs titers were under 10mIU/mL. Group A was revaccinated one dose of the same amount of the previous vaccine. Group B was given three doses of the same amount of the vaccine. Group C was given one double dose of the vaccine. The seroconversion rate and geometrical mean titer were measured one month later. RESULTS: Negative anti-HBs rate was 14.5% in children who had been vaccinated. The seroconversion rate was high in all revaccination groups(86.7-94.7%). Three doses of revaccination had no significant difference from one dose of revaccination. There was no positive effect of double dose of revaccination in comparison with the usual dose. CONCLUSION: In our study, one dose of hepatitis B vaccine is as effective as three doses or double dose of hepatitis B vaccine for the nonresponsive children. We recommend administering one dose of hepatitis B vaccine to those children whose three anti-HBs titer is under 10mIU/mL and examining of the anti-HBs titer one month later after revaccination.