ACUTE NON-A, NON-B-HEPATITIS IN ITALY - A 16-YEAR PROSPECTIVE EPIDEMIOLOGIC-STUDY - THE POSSIBLE ROLE OF HEPATITIS-C VIRUS

During a survey of acute symptomatic viral hepatitis conducted in Padu a over the last 16 years, 404 (20%) cases of non-A, non-B hepatitis we re observed, including 55% with overt parenteral exposure (35% drug ab users) and 45% with unknown exposure. Between 1978 and 1982 the attack rate of the disease increased significantly (p < 0.01) in males, (fro m 3.8 to 17.3/10(5) inhabitants), in adolescents and in youths. The pr evalence of drug abusers rose up to 58% in 1982 suggesting the occurre nce of an outbreak in this risk group. In subsequent Sears the attack rate returned to initial levels in males, although drug abuse still re mains the single most important route of infection, and declined in fe males, especially after the disappearance of post-transfusion hepatiti s since 1991. Retrospective anti-HCV testing of patients seen up to 19 90 and prospective investigation of patients hospitalized later have s hown an antibody prevalence of 88% among parenterally transmitted case s, and of 29% in the other patients, without significant differences b etween the prospective and the retrospective study These findings sugg est that an outbreak of hepatitis C occurred in our area in the early eighties and that drug abuse is still the most important mode of trans mission of acute hepatitis C.