Hepatitis C virus infection in Western Europe.

Hepatitis C virus (HCV) infection is now recognised as the most common infection causing chronic liver disease in Europe. Approximately 3% of the world population has been infected with HCV, which represents about 170 million chronic carriers at risk of developing serious complications with more than 5 million in Europe alone. In the general population, the prevalence varies geographically from about 0.5% in northern countries to 2% in Mediterranean countries. Among newly detected HCV cases, 40-60% have normal ALT levels, 80% are viraemic, while about 70% of newly detected HCV carriers present histologic liver disease. More than 75% of the cases remain to be identified. The residual risk for transmitting HCV by blood products is at present 1/200 000 units distributed. Intravenous drug users are currently the main risk group. The prevalence rate is about 80% and the yearly incidence varies between 4 and 6%. In haemodialysis patients, the prevalence ranges from 10% to 30% and the incidence from 3% to 7%. The source of infection for the 30% of cases without identifiable risk factor remains to be clarified and appropriate well-controlled case-control studies on large samples are necessary. Further training and information campaigns remain desirable to improve knowledge and awareness among health care professionals.