Epidemiology of sporadic acute non-A, non-B hepatitis in Japan: a comparison with hepatitis A and B.
Two hundred fifty-eight patients with clinically and serologically proven sporadic acute viral hepatitis during a period of past 7 years (January 1976-December 1982) were analyzed regarding epidemiology and outcome. The frequency of non-A, non-B (NANB) hepatitis was the highest among the three categories of viral hepatitis; 118 patients had hepatitis NANB (46%), 70 hepatitis A (27%), and 70 hepatitis B (27%). In NANB hepatitis, the mean age was older than in other categories of hepatitis and both sexes were equally affected, in contrast to the male predominance in types A and B. Chronic liver disease developed in 32% of patients with NANB hepatitis, but in none of patients with hepatitis type A or B. These results suggest that in Japan the infectious sources of hepatitis NANB virus(es) are more prevalent than those of hepatitis A and B viruses, and also suggest that one of the possible important factors for the high tendency to chronicity may be concerned with intimate contact with, or evolution from, asymptomatic NANB virus carriers.
D000293:Adolescent; D000328:Adult; D005260:Female; D006506:Hepatitis A / Q000453:epidemiology*; D006509:Hepatitis B / Q000453:epidemiology*; D006526:Hepatitis C / Q000453:epidemiology*; D006525:Hepatitis, Viral, Human / Q000453:epidemiology*; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged