title: The incidence and risk factors of community-acquired hepatitis C in a cohort of Italian blood donors.
abstract: To assess the incidence and source of community-acquired hepatitis C virus (HCV) infection among subjects at low risk for blood-borne diseases, we prospectively studied a cohort of 16,515 repeat blood donors over a mean follow-up time of 36 months. Second- and third-generation methods were used for hepatitis C virus antibody (anti-HCV) testing. HCV RNA was determined in the serum of anti-HCV-positive donors by reverse-transcription polymerase chain reaction. Liver biopsy was performed in the viremic subjects. Risk factors for HCV infection were identified by a psychosocial questionnaire in the whole cohort. During follow-up, 5 donors became infected with HCV. The incidence was 1 per 10,000 person-years (95% confidence interval, 0.3-2.4 per 10,000). During the 6 months before seroconversion, four subjects (80%) underwent medical or surgical percutaneous procedures, compared with 26.5% in the entire donor cohort (difference between frequencies, 53.5%; CI: 18.9-89.1). One seroconverting donor had sexual intercourse with an infected subject. Only 1 infected donor developed clinically evident acute hepatitis. HCV RNA remained detectable in 4 of 5 subjects for 8 to 36 months after seroconversion, and liver biopsy showed chronic hepatitis in all cases. Thus, new cases of hepatitis C occur among individuals without a history of known risk factors, some of which may be caused by nosocomial exposure.
authors.affiliation: Centro Trasfusionale e di Immunologia dei Trapianti, Ospedale Maggiore, Milano, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Prati
authors.forename: C
authors.initials: C
authors.lastname: Capelli
authors.forename: C
authors.initials: C
authors.lastname: Silvani
authors.forename: C
authors.initials: C
authors.lastname: De Mattei
authors.forename: P
authors.initials: P
authors.lastname: Bosoni
authors.forename: M
authors.initials: M
authors.lastname: Pappalettera
authors.forename: F
authors.initials: F
authors.lastname: Mozzi
authors.forename: M
authors.initials: M
authors.lastname: Colombo
authors.forename: A
authors.initials: A
authors.lastname: Zanella
authors.forename: G
authors.initials: G
authors.lastname: Sirchia
mesh_terms: D000328:Adult; D001782:Blood Donors; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000453:epidemiology / Q000821:virology; D005260:Female; D006526:Hepatitis C / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors