title: A pan-European survey of antimicrobial susceptibility towards human-use antimicrobial drugs among zoonotic and commensal enteric bacteria isolated from healthy food-producing animals.
abstract: OBJECTIVE
  The aim of the study was to study antimicrobial susceptibility in Escherichia coli, Salmonella, Campylobacter and Enterococcus recovered from chickens, pigs and cattle using uniform methodology.
  
  
  METHODS
  Intestinal samples were taken at slaughter in five EU countries per host and bacteria isolated in national laboratories. MICs were determined in a central laboratory of key antimicrobials used in human medicine. Clinical resistance was based on CLSI breakpoints and decreased susceptibility on EFSA epidemiological cut-off values.
  
  
  RESULTS
  Isolation rates from a total of 1500 samples were high for E. coli (n=1465), low for Salmonella (n=205) and intermediate for Campylobacter (n=785) and Enterococcus (n=718). Resistance prevalence varied among antibiotics, bacteria, hosts and countries. For E. coli and Salmonella, clinical resistance to newer compounds (cefepime, cefotaxime, ciprofloxacin) was absent or low, but a decreased susceptibility was apparent, particularly in chickens. Clinical resistance to older compounds (except colistin and gentamicin) was variable and higher. For Campylobacter jejuni from chickens, ciprofloxacin resistance was markedly higher than in isolates from cattle. Clinical resistance to erythromycin was absent for both hosts; decreased susceptibility very low. Similar trends were determined for Campylobacter coli, but C. jejuni was less resistant. None of the enterococcal strains was resistant to linezolid, but a few displayed resistance to ampicillin or vancomycin. Resistance prevalence to quinupristin/dalfopristin was clearly higher.
  
  
  CONCLUSIONS
  Antimicrobial resistance among enteric organisms in food animals varied among countries, particularly for older antimicrobials, but clinical resistance to essential compounds used to treat disease in humans was generally zero or low. In the absence of clinical resistance to newer compounds in E. coli and Salmonella, the apparent decreased susceptibility should be monitored carefully.
authors.affiliation: EASSA Study Group, c/o CEESA, 1 Rue Defacqz, Brussels, Belgium. anno.jong@bayerhealthcare.com
authors.forename: Anno
authors.initials: A
authors.lastname: de Jong
authors.forename: Robin
authors.initials: R
authors.lastname: Bywater
authors.forename: Pascal
authors.initials: P
authors.lastname: Butty
authors.forename: Erik
authors.initials: E
authors.lastname: Deroover
authors.forename: Kevin
authors.initials: K
authors.lastname: Godinho
authors.forename: Ulrich
authors.initials: U
authors.lastname: Klein
authors.forename: Hervé
authors.initials: H
authors.lastname: Marion
authors.forename: Shabbir
authors.initials: S
authors.lastname: Simjee
authors.forename: Katelijne
authors.initials: K
authors.lastname: Smets
authors.forename: Valérie
authors.initials: V
authors.lastname: Thomas
authors.forename: Michel
authors.initials: M
authors.lastname: Vallé
authors.forename: Aileen
authors.initials: A
authors.lastname: Wheadon
mesh_terms: D000818:Animals; D000829:Animals, Domestic / Q000382:microbiology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002417:Cattle; D002645:Chickens; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000302:isolation & purification*; D005062:European Union; D041981:Gastrointestinal Tract / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D013552:Swine
chemical_list: D000900:Anti-Bacterial Agents