Sero epidemiological characteristics of hepatitis C encountered in general practice in Belgium.

A study carried out between 1982 and 1984 established by exclusion diagnosis that 35% of viral hepatitis cases registered in Belgium were due to non A, non B (NANB) viruses. Recently, a new anti-hepatitis C virus (HCV) detection test was used to analyse the sera of patients in whom NANB hepatitis was diagnosed in that study. Using this new serological test for HCV, 29% of the NANB group was found to be positive for anti-HCV. In the 1982-84 study on viral hepatitis diagnosed by general practitioners, the number of clinically recognized infections was estimated at 14,700 (+/- 2,170; confidence interval at 95%) per year. By combining these data and the results of the present study, the following estimates could be calculated: HAV (7,129 +/- 1,054/year), HBV (2,426 +/- 358/year), HCV (1,470 +/- 216/year) and non-identified hepatitis viruses (3,675 +/- 543/year).