The investigation for the change of HBsAg positive rate of grade junior high high-schoolers for recent 3 years in Kangwon province

Jang, Myoung Kuk; Lee, Ja Young; Lee, Jin Heon; Kim, Yong Bum; Kim, Hak Yang; Yoo, Jae Young

Abstract

BACKGROUND
Since 1983, vaccination for Hepatitis B virus(HBV) has been recommended for all neonates in Korea. Therefore, significant change of HBsAg positive rate is expected. The objective of this study is to investigate HBsAg positive rate of grade, junior high, and high schoolers in Kangwon Province.
METHODS
From 1997 to 1999, total 120,220 subjects, who were born in 1981 to 1992, were enrolled in this study. HBsAg and anti-HBs were tested by reversed passive hemagglutination and passive hemagglutination, respectively. If their results had been vague, we perfomed enzyme-linked immunosorbent assay for confirmation.
RESULTS
HBsAg positive rate of entire study group was 2.5%(3,045 out of 120,220). Those of schoolboys and schoolgirls were 2.6%(1,567 out of 60,076), 2.5%(1,478 out of 60,144), respectively. Significant statistical difference was not observed in comparison of HBsAg positive rate according to sex(p=0.09). HBsAg positive rate of grade schoolers was 1.4%(676 out of 48,871), which was significantly lower than that of junior high(3.2%, 557 out of 17,577) and high-schoolers(3.4%, 1,812 out of 53,772)(p< 0.01). From 1997 to 1999, HBsAg positive rate has significantly decreased from 2.8%(1,434 out of 50,434) to 1.9%(407 out of 20,991)(p< 0.01). HBeAg positive rate of HBsAg positive subjects was 62.9%(1,000 out of 1,590).
CONCLUSION
HBsAg positive rate of grade-schoolers in Kangwon province Korea, tended to be lower than that of junior high, or high-schoolers, and is also thought to be lower than that of the past, which was caused by nationwide vaccination programme.