title: Carbapenem-resistant Klebsiella pneumoniae producing New Delhi metallo-β-lactamase at an acute care hospital, Colorado, 2012.
abstract: OBJECTIVE
  To investigate an outbreak of New Delhi metallo-β-lactamase (NDM)-producing carbapenem-resistant Enterobacteriaceae (CRE) and determine interventions to interrupt transmission.
  
  
  METHODS
  Epidemiologic investigation of an outbreak of NDM-producing CRE among patients at a Colorado acute care hospital.
  
  
  METHODS
  Case patients had NDM-producing CRE isolated from clinical or rectal surveillance cultures (SCs) collected during the period January 1, 2012, through October 20, 2012. Case patients were identified through microbiology records and 6 rounds of SCs in hospital units where they had resided. CRE isolates were tested by real-time polymerase chain reaction for blaNDM. Medical records were reviewed for epidemiologic links; relatedness of isolates was evaluated by pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS). Infection control (IC) was assessed through staff interviews and direct observations.
  
  
  RESULTS
  Two patients were initially identified with NDM-producing CRE during July-August 2012. A third case patient, admitted in May, was identified through microbiology records review. SC identified 5 additional case patients. Patients had resided in 11 different units before identification. All isolates were highly related by PFGE. WGS suggested 3 clusters of CRE. Combining WGS with epidemiology identified 4 units as likely transmission sites. NDM-producing CRE positivity in certain patients was not explained by direct epidemiologic overlap, which suggests that undetected colonized patients were involved in transmission.
  
  
  CONCLUSIONS
  A 4-month outbreak of NDM-producing CRE occurred at a single hospital, highlighting the risk for spread of these organisms. Combined WGS and epidemiologic data suggested transmission primarily occurred on 4 units. Timely SC, combined with targeted IC measures, were likely responsible for controlling transmission.
authors.affiliation: Epidemic Intelligence Service, Centers for Disease Control and Prevention, Atlanta, Georgia.
authors.forename: Erin E
authors.initials: EE
authors.lastname: Epson
authors.forename: Larissa M
authors.initials: LM
authors.lastname: Pisney
authors.forename: Joyanna M
authors.initials: JM
authors.lastname: Wendt
authors.forename: Duncan R
authors.initials: DR
authors.lastname: MacCannell
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Janelle
authors.forename: Brandon
authors.initials: B
authors.lastname: Kitchel
authors.forename: J Kamile
authors.initials: JK
authors.lastname: Rasheed
authors.forename: Brandi M
authors.initials: BM
authors.lastname: Limbago
authors.forename: Carolyn V
authors.initials: CV
authors.lastname: Gould
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Kallen
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Barron
authors.forename: Wendy M
authors.initials: WM
authors.lastname: Bamberg
mesh_terms: D000328:Adult; D000368:Aged; D015780:Carbapenems / Q000494:pharmacology / Q000627:therapeutic use*; D003120:Colorado; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial; D005260:Female; D006761:Hospitals; D006801:Humans; D007710:Klebsiella Infections / Q000188:drug therapy* / Q000453:epidemiology; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000201:enzymology / Q000235:genetics; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D017422:Sequence Analysis, DNA; D055815:Young Adult; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D015780:Carbapenems; D001618:beta-Lactamases; C552864:beta-lactamase NDM-1