Investigation on Contamination Caused by Listeria in foods

Objective This investigation was to learn about the contamination status caused by Listeria in foods in Guangzhou city. Methods A total of 150 samples sold in large-scale supermarkets and on the market including cooked food, raw meat, milk produce, ice cream and pastry, as well as vegetable and salad was randomly collected from June of 2003 to June of 2004 for determination of Listeria, the drug resistance of Listeria monocytogenes found from which was also investigated. Results 9 strains of Listeria were detected, with a total detectable rate of 6.00%, of which cooked food and raw meat accounted for 6.67% and 17.39%, respectively; one strain of 9 that had been detected was Listeria monocytogenes which was not found in other samples. Conclusion Contamination of Listeria by various degrees exists in food of Guangzhou and we should strengthen surveillance and monitoring to preclude the outbreak and epidemic of food poisoning caused by Listeria.