All issues > Volume 29(6); 1986

Original Article

J Korean Pediatr Soc. 1986;29(6):613-625. Published online June 30, 1986.

Epidemiologic Study on Hepatitis B Virus Infection in Childhood.

Byoung Tae Kim¹

¹Department of Pediatrics，College of Medicine, Soon Chun Hyang University

Abstract

We conducted HBsAg, HBsAb and HBcAb determinations by the method of radioimmunoassay on 329 healthy children who visited for the purpose of immunization with HB vaccine, or had been admitted because of miscellaneous diseases except for liver disease from July 1984 to December 1984. The following results were obtained; 1) Among the 329 children, 16(4.9%) were positive for HBsAg. There was no sex difference (5.4% in males, 4.2% in females). Prevalence of HBsAg increased with increment of age reaching 8.6% at the age group of 12〜 15 years. 2) Among- the 329 children, 32(9.7%) were positive for HBsAb. There was no sex difference (10.8% in males, 8.3% in females). 3) Among the 204 children, 29(14.2%) were positive for HBcAb. There was no sex difference(14.0% in males, 14.5% in females). Prevalence of HBcAb increased with increment of age, reaching 30.8% at the age group of 12〜 15 years. These results suggested that (a) hepatits B virus infection is acquired early in Korean population and increases with age, (b) to protect these children, early immunization with HB vaccine is imperative. We conducted a study to compare serologic data on the risk of HB infection in 12 families, each with an asymptomatic HBsAg-positive child (contact group) and 30 families without an asymptomatic HBsAg-positive child (control group) by radioimmunoassay. The following results were obtained; 1) Among 39 cases of the contact group, 13(33.3%) were positive for HBsAg, and 12(30.8 %) were positive for HBsAb. Among 90 cases of the control group, 6(6.7%) were positive for HBsAg, and 23(25.6%) were positive for HBsAb 2) Prevalence of HBsAg in the mothers, siblings and fathers of the contact group were 41.7%, 40.0% and 16.7%, respectively. Prevalence of HBsAg in the mothers, siblings and fathers of the control group were 6.7%, 0% and 13.3%, respectively. (p<0.05 in mothers and siblings). 3) Prevalence of HBsAb in the mothers, siblings and fathers of the contact group were 33.3%, 13.3% and 50.0%, respectively. Prevalence of HBsAb in the mothers, siblings and fathers of the control group were 33.3%, 6.7% and 36.7%, respectively. These results suggested that (a) the risk of hepatitis B infection is higher in households of an asymptomatic HBsAg-positive child than those of a HBsAg-negative child, (b) HBsAg carrier mothers and siblings are highly suspected as sources of HB virus infection to children. A study on the prevalence of HBsAg in cord blood, gastric aspirate and newborn* s blood born to HBsAg-positive mothers was carried out by the method of radioimmunoassay. Also 11 babies born to HBsAg-positive mothers were followed up for HBsAg appearance. Another 6 babies born to HBsAg-positive mothers were treated with HBIG at 0,3 and 6 month of age and HB vaccine at 3,4 and 9 month of age. The following results were obtained; 1) The positive rates of HBsAg were 48.5% (32/66) in cord blood, 26.7% (16/60) in gastric aspirate and 4.8%(1/21) in newborn*s blood. The positive rates of HBsAg in cord blood and gastric aspirate were higher in cases born to HBeAg-positive mothers than in those born to HBeAg-negative mothers(p<0.05). 2) Among 11 babies born to HBsAg-positive mothers, 7(63.6%) became HBsAg-positive. The perinatal transmission was higher in 6 babies born to HBeAg-positive others(100%) than in 5 babies born to HBeAg-negative mothers (20%), indicating that HBeAg is an important factor in perinatal transmission. 3) Among 6 babies treated with HBIG and HB vaccine, all became HBsAb-positive without HBs antigenemia.

Keywords :Hepatitis B; Prevalence in children; Familial clustering; Perinatal transmission.