Fresh leafy green vegetables associated with multidrug resistant E.coli


  • Shereen Z. Burjaq Department of Pathology, Microbiology and Forensic Medicine, Faculty of Medicine, University of Jordan, Amman, Jordan.
  • Asem A. Shehabi


Background: Recent outbreaks of  E. coli diarrheal diseases linked to the consumption of  fresh green produce, has raised a global concern about bacterial pathogens that cause food borne diseases. While little attention have been devoted to contamination of fresh green food with drug resistance bacteria species.

Objective: To detect the occurrence of contamination and antibiotic resistance in E. coli isolates from fresh leafy vegetables presented in Jordanian retail markets.

Study design: A total 150 fresh leafy green vegetable samples were collected from different markets in Amman and Al-Zarqa in Jordan over the five months; June through October, 2010  .

Results: A total of 61 (40.6%) E. coli isolates were found as contaminates of 150 fresh leafy green vegetable samples. The highest contamination with E. coli occurred in parsley and lowest in Lettuce.  A range of  3-41% of E. coli isolates were resistant to 7 common antibiotics used often in the treatment of urinary tract infection in Jordan. A total of 17 (27.8%) E. coli isolates were resistant to three or more antimicrobial agents and considered to be multidrug resistant. Of these, 14(82%) isolates were positive for class 1 integron, 17(100%) carry at least one plasmid with a common sizes (7.3 and 54.3 Kb), 12(70.6%),  and  2(11.8%) isolates were positive for Tet A and Tet B genes, respectively. A total of 15 (88.2%) isolates were positive for sul2 and 4 (23.5%) isolates for sul1 gene.

Conclusion: This study demonstrates the widespread of antimicrobial resistance in E. coli contaminating fresh green produce and which may increase the reservoir of antimicrobial resistance in the intestinal tract of Jordanian population.


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