title: Hepatitis C virus infections from unsafe injection practices at an endoscopy clinic in Las Vegas, Nevada, 2007-2008.
abstract: BACKGROUND
  In January 2008, 3 persons with acute hepatitis C who all underwent endoscopy at a single facility in Nevada were identified.
  
  
  METHODS
  We reviewed clinical and laboratory data from initially detected cases of acute hepatitis C and reviewed infection control practices at the clinic where case patients underwent endoscopy. Persons who underwent procedures on days when the case patients underwent endoscopy were tested for hepatitis C virus (HCV) infection and other bloodborne pathogens. Quasispecies analysis determined the relatedness of HCV in persons infected.
  
  
  RESULTS
  In addition to the 3 initial cases, 5 additional cases of clinic-acquired HCV infection were identified from 2 procedure dates included in this initial field investigation. Quasispecies analysis revealed 2 distinct clusters of clinic-acquired HCV infections and a source patient related to each cluster, suggesting separate transmission events. Of 49 HCV-susceptible persons whose procedures followed that of the source patient on 25 July 2007, 1 (2%) was HCV infected. Among 38 HCV-susceptible persons whose procedures followed that of another source patient on 21 September 2007, 7 (18%) were HCV infected. Reuse of syringes on single patients in conjunction with use of single-use propofol vials for multiple patients was observed during normal clinic operations.
  
  
  CONCLUSIONS
  Patient-to-patient transmission of HCV likely resulted from contamination of single-use medication vials that were used for multiple patients during anesthesia administration. The resulting public health notification of approximately 50,000 persons was the largest of its kind in United States health care. This investigation highlighted breaches in aseptic technique, deficiencies in oversight of outpatient settings, and difficulties in detecting and investigating such outbreaks.
authors.affiliation: National Center for HIV, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA. fez7@cdc.gov
authors.forename: Gayle E
authors.initials: GE
authors.lastname: Fischer
authors.forename: Melissa K
authors.initials: MK
authors.lastname: Schaefer
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Labus
authors.forename: Lawrence
authors.initials: L
authors.lastname: Sands
authors.forename: Patricia
authors.initials: P
authors.lastname: Rowley
authors.forename: Ihsan A
authors.initials: IA
authors.lastname: Azzam
authors.forename: Patricia
authors.initials: P
authors.lastname: Armour
authors.forename: Yury E
authors.initials: YE
authors.lastname: Khudyakov
authors.forename: Yulin
authors.initials: Y
authors.lastname: Lin
authors.forename: Guoliang
authors.initials: G
authors.lastname: Xia
authors.forename: Priti R
authors.initials: PR
authors.lastname: Patel
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Perz
authors.forename: Scott D
authors.initials: SD
authors.lastname: Holmberg
mesh_terms: D000328:Adult; D000368:Aged; D016000:Cluster Analysis; D003428:Cross Infection; D004196:Disease Outbreaks; D004724:Endoscopy / Q000009:adverse effects*; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D006526:Hepatitis C / Q000175:diagnosis* / Q000453:epidemiology*; D006801:Humans; D007049:Iatrogenic Disease; D007267:Injections / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D009505:Nevada / Q000453:epidemiology