Ten year incidence of HCV infection in northern Italy and frequency of spontaneous viral clearance

• Published in: Gut Vol. 52; no. 7; pp. 1030 - 1034
• Main Authors: Mazzeo, C, Azzaroli, F, Giovanelli, S, Dormi, A, Festi, D, Colecchia, A, Miracolo, A, Natale, P, Nigro, G, Alberti, A, Roda, E, Mazzella, G
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and British Society of Gastroenterology 01.07.2003; BMJ; BMJ Publishing Group Ltd; BMJ Publishing Group LTD; Copyright 2003 by Gut
• Subjects: Adolescent; Adult; Age; Aged; alanine aminotransferase; Algorithms; ALT; Antibodies, Viral - analysis; Biological and medical sciences; Cohort Studies; Demographic aspects; Demographics; Development and progression; epidemiology; Family Health; Female; general population; Genotype; Genotype & phenotype; HCV; HCV antibody; HCV-Ab; Hepatitis; Hepatitis C; Hepatitis C - enzymology; Hepatitis C - epidemiology; Hepatitis C - virology; hepatitis C virus; Human viral diseases; Humans; IFN; Incidence; Infections; Infectious diseases; interferon α; Italy - epidemiology; Liver; Liver diseases; Male; Medical geography; Medical sciences; Middle Aged; optical density; Physicians; Population; Prevalence; Remission, Spontaneous; reverse transcriptase-polymerase chain reaction; Risk Factors; RNA, Viral - analysis; RT-PCR; Rural Health; Studies; viral clearance; Viral diseases; Viral hepatitis; Virus-vector relationships; Italy; Europe; Human; Hepatic disease; Genotype; Biology; Clearance; Biliary tract disease; Epidemiology; Incidence; Infection; Choledoch; Viral disease; Cohort study; Lithiasis; Digestive diseases; North; Viral load; Viral hepatitis C
• ISSN: 0017-5749; 1468-3288; 1458-3288
• DOI: 10.1136/gut.52.7.1030

Background: Little is known of the incidence of hepatitis C virus (HCV) infection, and the frequency of spontaneous viral clearance in the general population is unknown. We conducted an epidemiological study in two Apennine towns in northern Italy. Methods: Anti-HCV (ELISA and RIBA third generation) and HCV-RNA by polymerase chain reaction were tested in thawed sera from an adult general population of Loiano-Monghidoro in 1986 and 1996, obtained in the context of the MICOL (Multicenter Italian Study on Cholelithiasis). In 1999, anti-HCV positive subjects and sex and age matched controls were recalled in order to identify risk factors for acquiring HCV infection and to assess the family composition of anti-HCV+ subjects. Results: For 1646 subjects, sera were available from both 1986 and 1996 (mean age in 1986 43 (0.39) years). In 1986, 57 (3.46%) subjects were HCV antibody positive (HCV-Ab+). Eight new cases were recorded in 1996: adult incidence was 50.3 cases/100 000 inhabitants/year. Fifty three of 63 (84.1%) HCV-Ab+ sera were also HCV-RNA+. Genotype 2a/2c accounted for 44% and 1b for 47.0% of cases. HCV-Ab+ subjects had higher serum levels of alanine aminotransferase with respect to controls (p<0.005), as did subjects infected with genotype 1 with respect to those with genotype 2 (p<0.05). Eleven of 65 (16.9%) HCV-Ab+ subjects spontaneously cleared HCV-Ab; 7/11 also lost HCV-RNA− in both serum and leucocytes. Sixteen anti-HCV+ subjects belonged to families containing more than one infected member. Married couples accounted for 10 of these 16 subjects. In four of these five married couples, HCV genotype was identical in the two spouses. Conclusions: In rural northern Italy, the adult incidence of HCV is approximately 50 cases/100 000 inhabitants/year. Our findings suggest that as many as 17% of infected subjects may spontaneously clear HCV-Ab. Interfamilial transmission seems to have a role in the spread of infection.