title: Carriage of ESBL/AmpC-producing or ciprofloxacin non-susceptibleEscherichia coliandKlebsiellaspp. in healthy people in Norway.
abstract: BACKGROUND
  Asymptomatic carriage has been recognised as an important risk factor for infection caused by antibiotic resistant bacteria. A 14% global prevalence of Extended-Spectrum Beta-lactamase (ESBL) carriage was recently reported, but large intra-and interregional variations were observed. We investigated the faecal carriage rates of ESBL-, AmpC-producing and ciprofloxacin non-susceptibleEscherichia coliandKlebsiellaspp. in healthy Norwegians.
  
  
  METHODS
  Rectal samples were obtained from 284 volunteers, together with demographic data and information on recent travel history. The rectal samples were screened by selective plating andE. coliandKlebsiellaspp. identified using MALDI-TOF. Phenotypic and molecular characterization of resistant isolates was also performed.
  
  
  RESULTS
  ESBL- or AmpC-producingE. coliandKlebsiellaspp. were isolated from 4.9% and 3.2% of the study population, respectively. Carriage of ciprofloxacin non-susceptible isolates was detected in 9.9% of the volunteers. Molecular typing of ESBL/plasmid-mediated AmpC (pAmpC)-producing isolates suggested an allodemic situation rather than the dissemination of a specific clone in the Norwegian community. In concurrence with previous findings, travel to South-East Asia was associated with increased risk of carrying resistantE. coliorKlebsiellaspp., highlighting the contribution of factors such as increased global mobility in erasing the boundaries between healthcare and community settings when it comes to spread of resistant bacteria.
  
  
  CONCLUSIONS
  Overall, our study recognised Norway as a low-incidence country for faecal carriage of resistant bacteria among healthy individuals. Furthermore, our work denoted the importance of healthy humans as a reservoir for transmission of antibiotic resistantE. coliandKlebsiellaspp.
authors.affiliation: Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Charlotte R
authors.initials: CR
authors.lastname: Ulstad
authors.affiliation: Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Margrete
authors.initials: M
authors.lastname: Solheim
authors.affiliation: Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Sophie
authors.initials: S
authors.lastname: Berg
authors.affiliation: Institute of Health and Society, University of Oslo, Oslo, Norway.
authors.forename: Morten
authors.initials: M
authors.lastname: Lindbæk
authors.affiliation: Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Ulf R
authors.initials: UR
authors.lastname: Dahle
authors.affiliation: Domain for Infection Control and Environmental Health, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Astrid L
authors.initials: AL
authors.lastname: Wester
keywords: Ciprofloxacin; ESBL; Escherichia coli; Faecal carriage; Klebsiella; Norway