Hepatitis C virus infection in Italian intravenous drug users: epidemiological and clinical aspects.

The epidemological and clinical features of hepatitis C virus infection have been evaluated in a cohort of 227 intravenous drug users enrolled at a drug dependence treatment center in the Veneto area in 1992-1993 and followed periodically. Hepatitis C virus infection was detected using second-generation anti-HCV ELISA in 171 (75%) subjects at enrollment. Anti-HCV seropositivity correlated with: a) the duration of drug abuse: 91% of intravenous drug users injecting for more than 8 years were seropositive as compared to 40% of those with a history of abuse lasting 4 years or less, p < 0.001; b) sharing of injection equipment: 85% anti-HCV positive intravenous drug users had shared at some time as compared to 64% seronegative subjects, p < 0.001; c) seropositivity for immunodeficiency virus infection: 25% anti-HCV positive intravenous drug users were coinfected as compared to 3.5% anti-HCV negative, p < 0.001; d) markers of ongoing (two cases) or previous hepatitis B virus infection were detected in 62% of anti-HCV positive but in 21% of anti-HCV negative cases, p < 0.01. Two initially anti-HCV negative intravenous drug users seroconverted during follow up giving an incidence rate of hepatitis C virus infection of 6.2 per 100 person-years. During the survey abnormal alanine aminotransferase levels were detected in 75% anti-HCV positive but in 24% anti-HCV negative cases (p < 0.001), with significantly higher levels in the former. These findings suggest that the circulation of hepatitis C virus among intravenous drug users has been decreasing in recent years, although new infections still occur.(ABSTRACT TRUNCATED AT 250 WORDS)

Patterns of antibodies to hepatitis C virus and hepatitis C virus replication in children with chronic non-A, non-B hepatitis.

Antibodies to hepatitis C virus (HCV), investigated by second- and third-generation assays, were detected in 74% of 43 children with chronic non-A, non-B hepatitis. The polymerase chain reaction identified HCV ribonucleic acid in 26 (93%) of 28 seropositive and in 1 of 10 seronegative cases. Intermittent HCV ribonucleic acid positivity, suggesting low and fluctuating viremia, was frequent in younger patients.

Acute non-A, non-B hepatitis in Italy: a 16-year prospective epidemiological study. The possible role of hepatitis C virus.

During a survey of acute symptomatic viral hepatitis conducted in Padua over the last 16 years, 404 (20%) cases of non-A, non-B hepatitis were observed, including 55% with overt parenteral exposure (35% drug abusers) and 45% with unknown exposure. Between 1978 and 1982 the attack rate of the disease increased significantly (p < 0.01) in males, (from 3.8 to 17.3/10(5) inhabitants), in adolescents and in youths. The prevalence of drug abusers rose up to 58% in 1982 suggesting the occurrence of an outbreak in this risk group. In subsequent years the attack rate returned to initial levels in males, although drug abuse still remains the single most important route of infection, and declined in females, especially after the disappearance of post-transfusion hepatitis since 1991. Retrospective anti-HCV testing of patients seen up to 1990 and prospective investigation of patients hospitalized later have shown an antibody prevalence of 88% among parenterally transmitted cases, and of 29% in the other patients, without significant differences between the prospective and the retrospective study. These findings suggest 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 transmission of acute hepatitis C.