Background & Aims: Shiga toxin-producing Escherichia coli (STEC), has appeared universally as an important zoonotic food-borne pathogen. Infection with STEC in human has different clinical picture, from mild secretory diarrhea, to hemorrhagic colitis (HC) which can lead to life threatening sequelae like haemolytic uremic syndrome. The purpose of this study was to determine antibiotic resistance profile of shiga toxin-producing E. coli (STEC), molecular identification, and antibacterial activity of Zataria multiflora bioss and Carum copticum essential oil against them.

  Materials & Methods: In this study, two hundred fecal samples were taken from Buffalo in West Azarbaijan province and examined for Shiga Toxin-producing Escherichia coli by PCR. Antimicrobial susceptibility of the isolates was considered by the disk diffusion method.

  Results: The results showed that 13 (8/6 %) of isolates harbored the Shiga toxin genes, containing three (23 %) was positive for stx₁ and stx_2, 5 (38%) was positively identified for stx₁, and 5 (38%) was positive for stx₂. Multi-drug resistance was detected in all STEC strains, all STEC were resistant to Ampicillin, neomycin, streptomycin, erytromycin, kanamycin, amoxicillin . Tobramycin,Cefotoxime and tetracycline were most effective and all STEC isolates were susceptible to them.

  Conclusion: According to the results buffalo has important role as a resorvior for STEC in Iran. On the other hand, the isolates showed a high rate of resistance to anti-microbial agents and multi-drug resistance was remarkably common. Finally, the antibacterial activity of plant essential oil would warrant further studies on the clinical applications.   

  Source: Urmia Med J 2011: 22(3): 270 ISSN: 1027-3727