Detection of E. coli O157:H7 in Meat Using Polymerase Chain Reaction Method and Culture Method

Escherichia coli O157:H7, as a pathogenic agent, can be transmitted through the foods including meat, meat products, dairy products, vegetables and water. The World Health Organization has recommended that all countries in the world, especially developing countries, should consider the investigation of E. coli O157:H7 as a research priority. The aim of this study was to determine the frequency of E. coli O157:H7 in meat of cow, sheep, goat, and camel in Kerman province of Iran using culture and polymerase chain reaction (PCR) methods.

In this study, 280 meat samples consisting of sheep (90 specimens), cow (80 specimens), goat (60 specimens) and camel (50 specimens) meats were randomly separated from carcasses from April to July 2018. After the sampling, microbial culture was performed on the samples. Then, suspected E. coli O157:H7 colonies were evaluated by PCR assay.

Out of the 280 samples, 73 samples (26%) were contaminated with E. coli. based on bacteriological tests, and 28 samples were identified as suspected E. coli O157:H7 serotype based on the lack of sorbitol fermentation. Subsequently, sorbitol-negative samples were tested by PCR procedure using specific primers. The results revealed that out of 28 cases, 21 cases (7.5%) were E. coli O157:H7.

As can be deduced from the observations of this study, to detect the E. coli O157, PCR as an accurate, fast, and reliable procedure can be used along with the culture method.