The prevalence of anti-HCV and serological markers of HBV infection was tested in 100 unselected intravenous drug addicts admitted to a detoxification ward. Anti-HCV were present in 78% addicts, and at least one markers of HBV infection was present in 69% addicts. No correlation was found between anti-HCV status and age, gender, duration of addiction or anti-HIV presence. Furthermore, there was no difference in mean titres of anti-CMV and anti-HSV between subjects with and without anti-HCV what suggests that the anti-HCV tested were specific.