title: An incident case-control study of modes of hepatitis C virus transmission in France.
abstract: OBJECTIVE
  Risk factors for hepatitis C virus (HCV) infection have rarely been estimated using incident case-control studies in the "general" population. We undertook a case-control study of incident HCV infection to identify persistent modes of transmission in France.
  
  
  METHODS
  Two types of case-patients were included: (1) repeat blood donors who seroconverted between 1998 and 2001 (with a last negative third-generation test reported from 1995 or after) and (2) seroconverters referred to hepatology departments in 2000 through 2001. For each case-patient, four age- and sex-matched controls were randomly selected from the population of occurrence. Data on risk factors were recorded for each case-patient's and matched control's referent exposure period (between last negative and first positive tests).
  
  
  RESULTS
  Sixty-four case-patients and 227 controls were included. In univariate analysis, endoscopy (matched odds ratios [mORs] = 8.0; 95% confidence intervals [CI] = 2.3-27.2), general anesthesia (mOR = 5.6; 95% CI = 2.2-14.7), tattooing or body piercing (mOR = 8.8; 95% CI = 1.7-44.1), and intravenous (IV) drug use (p < 0.0001; mOR not defined) were associated with HCV seroconversion. In multivariate analysis, risk factors associated with HCV seroconversion were drug use (adjusted OR [aOR] = 109.0; 95% CI = 11.7-1015.8), digestive endoscopy (aOR = 5.7; CI = 1.4-23.8), and invasive radiology procedures (aOR = 11.6; CI = 1.7-78.5).
  
  
  CONCLUSIONS
  The results showed the continuing major role of IV drug use and suggested that transmission related to invasive health care remained a potential source of new HCV infection between 1995 and 2001.
authors.affiliation: From the Institut de Veille Sanitaire, Saint-Maurice cedex, France. e.delarocque@invs.sante.fr
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Delarocque-Astagneau
authors.forename: Josiane
authors.initials: J
authors.lastname: Pillonel
authors.forename: Henriette
authors.initials: H
authors.lastname: De Valk
authors.forename: Alberto
authors.initials: A
authors.lastname: Perra
authors.forename: Syria
authors.initials: S
authors.lastname: Laperche
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Desenclos
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D005602:France / Q000453:epidemiology; D016174:Hepacivirus; D006526:Hepatitis C / Q000453:epidemiology* / Q000635:transmission*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D011795:Surveys and Questionnaires