Appearance Rat of HBs Antibody and One‐Year Change in Administration of HB Vaccine

Abstract

In order to prevent vertical infection between mother and infant with HBV, a method of giving passive immunity by anti‐HB human immune globulin just after birth and then active immunity by means of HB vaccine has been initiated. However, the sustained effect of antibody acquired through HB vaccine is not ascertained. In this study, we examined the appearance rate of anti‐HBs titer and its sustained effect by administering HB vaccine three times. Anti‐HBs appeared in all 13 cases by five months after birth, after the injection of HB vaccine three times. The titer was from 64 to 1,024. However, nine months after birth, there was a reduction of 1–2 tubes, and antibody titer was 64 to 512. Twelve months after birth a further reduction of 1–2 tubes was observed. In those cases in which anti‐HBs titer was under 256 at six months, by 12 months it decreased to 16–32. In such cases, a booster injection 12 months after birth was considered necessary. GOT and GPT showed changes within the normal range, and no local reaction at the injection site was found.