The prevalence of hepatitis C virus (HCV) infection increases with advancing age, but the disease has been poorly studied in the elderly. A population-based study was therefore carried out to investigate the prevalence of HCV infection and the severity of HCV-related chronic liver disease in the elderly. One thousand and sixty-three people (> or = 60 years of age) were screened for antibodies to HCV (anti-HCV) and for possible abnormalities of common liver function tests. Positive subjects and sex and age-matched anti-HCV-negative controls were recalled 12 months later for measurements of liver enzymes, confirmatory testing of anti-HCV, HCV RNA analysis and HCV genotyping. All subjects answered a specific questionnaire concerning medical history and possible risk factors. Forty-four subjects were positive for anit-HCV, the prevalence being 4.1%. Thirty-five positive subjects and 35 controls were investigated further. Risk factors for acquiring HCV were found to be: blood transfusion, surgical intervention and the use of non-disposable syringes. Abnormal alanine aminotransferase levels were found in 13 patients (37.1%). HCV RNA genotyping showed type 1b in three (15.8%), type 2a in 13 (68.4%) and not classified in three (15.8%) patients. There was no relationship between abnormalities of serum aminotransferase, the rate of HCV RNA positivity and HCV genotypes. Ultrasound abnormalities were present in 13 (37.1%) patients. In this elderly population the relatively high prevalence of HCV infection was thought to be caused by previous parenteral exposure. The low incidence of liver disease could be related to the prevalence of HCV genotype 2a in the majority of these patients, and hints at the possibility of an HCV carrier state in elderly individuals.