All issues > Volume 30(11); 1987

Original Article

J Korean Pediatr Soc. 1987;30(11):1221-1227. Published online November 30, 1987.

Immunogenecity of Low-Dose Administration of Hepatitis B Virus Vaccine in School Aged Group.

Young Mo Sohn¹, Pyung Kin Kim¹, Kyung Soon Song²

¹Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea
²Department of Clinical Pathology, Yonsei University College of Medicine, Seoul, Korea

Abstract

For evaluation of immunogenecity of low-dose of hepatitis vaccine-prepared by Korea Green Cross Corporation 74 school aged children were given routine schedule (0, 1, 6 months). A dose of 5 microgram was administered intramuscullary in the cases of age under 10 yrs of age and 10 microgram was administered in the cases over 11 yrs of age. An adequate follow-up observation of antibody titer by RIA was possible at 1, 2, 6, 7, 12 months after the first injection. In addition, we followed up anti-HBs titer of 45 children whose anti-HBs was positive at the screening survey. The results were as followes: 1) The anti-HBs positive rate was 95.6% (43/45) in the 5 microgram group and 100% (29/29) in 10 microgram group at the time of 12 months after the first injection. The effective rate (seroconversion rate 10 R.U.) was 68.9% (31/45) in the 5 microgram group and 79.3% (23/29) in the 10 microgram group. 2) The geometric mean anti-HBs titer at the 12 months after the first injection was 24.3 R.U. in 5 microgram group and 37.3 R.U. in the 10 microgram group. 3) Seronegative conversion rate of the children who has isolated anti-HBs at screening survey was 23.8% (5/21) at 12 months later. Especially 80% of seroconversion rate was observed in the 5 cases who had anti-HBs titer below 10 R.U. According to the above results, we have evaluated the low-dose administration of hepatitis Bvaccine in school aged children was effective for immunogenecity of this vaccine. But further follow-up of antibody titer must be evaluated and we found that in the most of isolated low titeranti-HBs cases, their antibody disappeared within 12 months.

Keywords :Hepatitis B Vaccine; Immunogencity.