Analysis of Immunogenicity after Hepatitis B Vaccination in Korea by Literature Review

Roh, Hye Ok; Lee, Woo Gill; Sohn, Young Mo

Abstract

PURPOSE
Although hepatitis B vaccine has been available to general population in Korea since 1983, it was difficult to compare various types of hepatitis B virus(HBV) vaccines primarily due to the differences in vaccination schedule, dosage, test methods and seropositive antibody level. In this study we reviewed the results of previous studies published in Korea, which include antibody positive rates and antibody titers of various vaccines, and examined the immunogenicity of these HBV vaccines.
METHODS
Studies published in medical journals, university journals concerning antibody positive rates following hepatitis B vaccination were reviewed. Inclusion criteria were those studies in which seroprotective antibody rate of 10mIU/mL or the sample ratio unit of 10RU were used as the cut-off value and in which the test methods were RIA or ELISA. Exclusion criteria were; 1) unclear or inconsistent vaccine dosage, 2) no record of antibody titers or seroconversion rate, 3) no defined antibody rate or ratio for positive rating and 4)the vaccination schedule other than 0-1-2 months or 0-1-6 months.
RESULTS
23 out of 52 studies were subjected for the review for seroconversion rates. 1) As for the immunogenicity in each age group, the seroconversion rates of Hepaccine (Cheil Jedang) were 85.1% in infants, 83.3% in children and 62.7% in adults, indicating higher rates in infants and children compared to adults(p < 0.01). The seroconversion rates of Hepavax(Korea Green Cross) were 84.7%, 81.1% and 90.8%, indicating higher rates in infants and adults compared to children(p < 0.01). 2) The seroconversion rate of Hepavax was 85.6% with 0-1-6 mo. schedule, 78.5% with 0-1-2 no. schedule with a statistically significant difference(p < 0.01). 4) There was no difference of seroconversion rates between the two doses of Hepavax, 5µg and 10µg in infants and children. 5) In adults the seroconversion rates were 62.7% with Hepaccine, 90.8% with Hepavax, and 94.8% with Engerix-B(SmithKline Beecham).
CONCLUSION
In Korea, the incidence of chronic hepatitis B is high and changing the schedule in vaccination cannot contribute to the increase of the seroconversion rate. And in order to maximize immunogenicity, more effective vaccines as well as more proper vaccination methods should be used.