title: Molecular epidemiology of a hepatitis C virus epidemic in a haemodialysis unit: outbreak investigation and infection outcome.
abstract: BACKGROUND
  HCV is a leading cause of liver chronic diseases all over the world. In developed countries the highest prevalence of infection is reported among intravenous drug users and haemodialysis (HD) patients. The present report is to identify the pathway of HCV transmission during an outbreak of HCV infection in a privately run haemodialysis (HD) unit in Italy in 2005.
  
  
  METHODS
  Dynamics of the outbreak and infection clinical outcomes were defined through an ambi-directional cohort study. Molecular epidemiology techniques were used to define the relationships between the viral variants infecting the patients and confirm the outbreak. Risk analysis and auditing procedures were carried out to define the transmission pathway(s).
  
  
  RESULTS
  Of the 50 patients treated in the HD unit 5 were already anti-HCV positive and 13 became positive during the study period (AR = 28.9%). Phylogenic analysis identified that, all the molecularly characterized incident cases (10 out of 13), were infected with the same viral variant of one of the prevalent cases. The multivariate analysis and the auditing procedure disclosed a single event of multi-dose vials heparin contamination as the cause of transmission of the infection in 11 out of the 13 incident cases; 2 additional incident cases occurred possibly as a result of inappropriate risk management.
  
  
  CONCLUSIONS
  More than 30% of all HCV infections in developed countries results from poor application of standard precautions during percutaneous procedures. Comprehensive strategy which included: educational programmes, periodical auditing on standard precaution, use of single-dose vials whenever possible, prospective surveillance for blood-borne infections (including a system of prompt notification) and risk assessment/management dedicated staff are the cornerstone to contain and prevent outbreaks in HD CONCLUSIONS: The outbreak described should serve as a reminder to HD providers that patients undergoing dialysis are at risk for HCV infection and that HCV may be easily transmitted whenever standard precautions are not strictly applied.
authors.affiliation: Istituto Nazionale per le Malattie Infettive Lazzaro Spallanzani via Portuense 292 00149 Rome, Italy. simone.lanini@inmi.it
authors.forename: Simone
authors.initials: S
authors.lastname: Lanini
authors.forename: Isabella
authors.initials: I
authors.lastname: Abbate
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Puro
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Soscia
authors.forename: Franceso
authors.initials: F
authors.lastname: Albertoni
authors.forename: Walter
authors.initials: W
authors.lastname: Battisti
authors.forename: Amilacare
authors.initials: A
authors.lastname: Ruta
authors.forename: Maria R
authors.initials: MR
authors.lastname: Capobianchi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Ippolito
mesh_terms: D000368:Aged; D016000:Cluster Analysis; D003428:Cross Infection / Q000453:epidemiology* / Q000821:virology; D004196:Disease Outbreaks; D005260:Female; D005838:Genotype; D006436:Hemodialysis Units, Hospital; D016174:Hepacivirus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006526:Hepatitis C / Q000453:epidemiology* / Q000821:virology; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D016896:Treatment Outcome
chemical_list: D012367:RNA, Viral
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