Prevalence and characterization of class 1 integrons in Escherichia coli of poultry and human origin

Alexandra Vasilakopoulou, Mina Psichogiou, Leonidas Tzouvelekis, Panayiotis T Tassios, Chris Kosmidis, George Petrikkos, Eleftheria S Roma, Ekaterina Charvalos, Maria Passiotou, Athina Avlami, George L Daikos

Research output: Contribution to journalArticlepeer-review


A prospective study was conducted to determine the prevalence and the gene-cassette content of class 1 integrons in Escherichia coli of poultry and human origin. A total of 235 E. coli isolates were examined; 65 were derived from farm poultry, 80 from hospitalized, and 90 from nonhospitalized patients. Susceptibilities to a range of antimicrobial agents were determined by disk diffusion. Int1-specific polymerase chain reaction, conserved-segment polymerase chain reaction, and DNA sequencing were used to determine the presence, length, and content of integrons. The relatedness among the isolates was examined by pulsed-field gel electrophoresis of XbaI digests of genomic DNA. The integron carriage rate for poultry isolates was 49.2%, whereas the carriage rate for hospital isolates was 26.2% and for community 11.1%. Multidrug resistance (resistance to three or more classes of antibiotics) phenotypes were observed in 96.8% of the integron-positive isolates, whereas only 34.9% of nonintegron-carrying organisms were multidrug resistant (p < 0.001). Seven integron types ranging in size from 663 to 2674 bp were identified; six types were observed in poultry isolates, five in hospital, and three in community isolates. Each integron type carried a distinct gene-cassette combination. The most prevalent gene cassettes belonged to the aad and dfr families. Identical integrons were detected in E. coli of human and poultry origin. A large reservoir of integrons exists in E. coli of poultry origin. The horizontal transfer of class 1 integrons among bacteria of poultry and human origins may contribute in the dissemination of antimicrobial resistance.

Original languageEnglish
Pages (from-to)1211-8
Number of pages8
JournalFoodborne Pathogens and Disease
Issue number10
Publication statusPublished - Dec 2009


  • Animals
  • Blood/microbiology
  • DNA, Bacterial/chemistry
  • Disk Diffusion Antimicrobial Tests
  • Drug Resistance, Microbial/genetics
  • Drug Resistance, Multiple, Bacterial
  • Escherichia coli/classification
  • Foodborne Diseases/prevention & control
  • Gastrointestinal Tract/microbiology
  • Greece
  • Humans
  • Inpatients/statistics & numerical data
  • Integrons/genetics
  • Outpatients/statistics & numerical data
  • Phenotype
  • Polymerase Chain Reaction
  • Poultry/microbiology
  • Sputum/microbiology
  • Suppuration/microbiology
  • Urine/microbiology


Dive into the research topics of 'Prevalence and characterization of class 1 integrons in Escherichia coli of poultry and human origin'. Together they form a unique fingerprint.

Cite this