Presence of Escherichia coli O157:H7 in Dairy Farms located in Najaf, Baghdad, Kirkuk, and Erbil, Iraq

Document Type : Original Articles


1 Altoosi University College, Najaf, Iraq

2 Department of Dentistry, Al-Hadba University College, Mosul, Iraq

3 Department of Pharmacy, Al-Manara College For Medical Sciences, Maysan, Iraq

4 Anesthesia Techniques Department, Al-Mustaqbal University College, Babylon, Iraq

5 College of Technical Engineering, The Islamic University, Najaf, Iraq

6 Department of Optics Techniques, Dijlah University College, Al-Masafi Street, Al-Dora, Baghdad 00964, Iraq

7 Al-Nisour University College, Baghdad, Iraq

8 Nursing Department, Hilla University College, Babylon, Iraq

9 Al-Esraa University College, Baghdad, Iraq

10 Department of Nursing, Al-Zahrawi University College, Karbala, Iraq

11 Microbiology Research Group , College of Pharmacy, Al-Ayen University, Thi-Qar, Iraq


It has been approved that one of the most dangerous foodborne pathogenic bacteria is E. coli O157:H7, which is responsible for several infection and death cases worldwide. It is well documented that in the developing countries E. coli O157:H7 is considered the main causative pathogen of human gastrointestinal infections. Therefore, the current research was aimed to evaluate the prevalence of E. coli O157:H7 in dairy cattle's milk using a rapid method, in Iraq (Najaf, Baghdad, Kirkuk, and Erbil). Over a period of 6 months (During hot months) samples were obtained and investigated by culturing on selective media (CT-SMAC).  The multiplex PCR (m-PCR) also used for milk sample direct investigation. Using biochemical tests the recorded data showed that, 2 recognized isolates were E. coli, while the recorded data obtained from m-PCR assay revealed that none of the isolated E. coli was toxigenic E.coli O157:H7. The results of m-PCR on the milk samples revealed that 45 milk samples contained at least one of the following genes: O157, H7, stx1, stx2 genes. Also the results of the m-PCR revealed that 2 samples (raw milk) were toxigenic O157:H7 positive. In conclusion, to the best of authors' knowledge, this investigation was the first report on the prevalence of E. coli O157:H7 in the raw milk samples in Iraq. The results showed that the proportion of contaminated milk samples contaminated with E. coli O157:H7 identified in the current survey were similar to that the results of the previously published research from different dairy products across different countries in the Middle East region.


Main Subjects

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