Epidemiology of hepatitis C virus infection in a suburban Detroit community.

A serum analysis for antibodies to the hepatitis C virus (HCV) was performed on a group of patients in a large suburban Detroit community hospital. The first 50 anti-HCV-positive patients with clinically suspected chronic non-A, non-B hepatitis were studied. Blood transfusions (58%) and intravenous drug use (22%) were the source of infection in most of these patients. A significant difference in age-related epidemiology was observed (p = 0.001). A remote history of intravenous drug use or tattoo application was elicited in 55% of individuals less than 40 yr old. "Sporadic" transmission occurred in 28% of individuals older than 50 yr. Sixteen percent (8/50) had no identifiable risk factors. Five of these eight patients (63%) were born and raised outside North America. Eighty percent of the 35 persons who underwent liver biopsy were found to have either chronic active hepatitis or cirrhosis. Twenty-nine percent (5/17) of the patients with anti-HCV-related cirrhosis presented with hepatocellular carcinoma. None of the patients with noncirrhotic liver disease had a primary liver tumor. We conclude that a significant number of patients in suburban America with chronic hepatitis C have no identifiable risk factors for HCV. Sporadic transmission of hepatitis C may play an important role in patients with chronic HCV-related liver disease, especially among patients born and raised outside North America.