Hepatitis A virus infection in Taiwan. A hospital-based study.

One hundred and thirty-four healthy subjects and 220 patients with liver diseases were studied for antibody to hepatitis A virus (anti-HAV) with radio-immunoassay. The frequency of anti-HAV related closely to the age of healthy subjects; the rate of positivity increased with age, being 5.9% in those under four years, 13.3% in the late first decade and over 90% after the third decade. Taking meals at stalls with poor sanitary standards is suspected to cause the prevailing infection in teenagers, although a cohort effect due to environmental and socio-economic improvement can not be excluded. Anti-HAV was present in most patients with frequencies comparable to healthy subjects of the same age. It is concluded that in Taiwan the prevalent chronic liver diseases and hepatocarcinoma are unrelated to HAV infection and the patients are infected to an extent similar to healthy people of the same age.