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

ABSTRACT

It has been approved that one of the most dangerous foodborne pathogenic bacteria is E. coli O157H7, which is responsible for several infection and death cases worldwide. It is well documented that in the developing countries E. coli O157H7 is considered the main causative pathogen of human gastrointestinal infections. Therefore, the current research was aimed to evaluate the prevalence of E. coli O157H7 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 O157H7. 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 O157H7 positive. In conclusion, to the best of authors' knowledge, this investigation was the first report on the prevalence of E. coli O157H7 in the raw milk samples in Iraq. The results showed that the proportion of contaminated milk samples contaminated with E. coli O157H7 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.