THE EPIDEMIOLOGY OF HEPATITIS B ANTIGEN IN A HIGH PREVALENCE AREA

Abstract

Punyagupta, S., L. C. Olson, U. Harinasuta, K. Akarawong and W. Varawidhya (Dept. of Medicine, Ramathibodi Faculty of Medicine, Bangkok, Thailand). The epidemiology of hepatitis B antigen in a high prevalence area. Am J Epidemiol 97: 349–354, 1973.—Hepatitis B antigen (HBAg) is found in the serum of about 10% of Thai adults. Infection is probably acquired during the first five years of life and persists for many years. Children positive for HBAg are more commonly found in families in which an older member is also HBAg-positive, suggesting that family contact is an important source of infection. It is estimated that at least 5% of chronically infected persons have associated inflammatory liver disease. Despite apparent frequent exposure, HBAg retains its common association with acute hepatitis, both in adults (57% of 181 patients) and in children (20% of 41 patients). HBAg was also found to be present in 25% of 60 patients with primary liver cell carcinoma. That the majority of Thai adults are not susceptible to HBAg associated hepatitis, however, is suggested by the finding that of 23 patients who developed detectable serum levels of HBAg or hepatitis B antibody after blood transfusion, only two developed hepatitis. The other patients demonstrated either transient antigenemia (7 patients) or an antibody response (14 patients).