The prevalence of bacterial contamination of table eggs from retails markets by Salmonella spp., Listeria monocytogenes, Campylobacter jejuni and Escherichia coli in Shahrekord, Iran

Introduction and objective: Contaminated egg and its products are increasing the risks of illness in humans. The significance of these diseases in humans can vary from mild symptoms to life threatening conditions. This study was conducted to determine the contamination of egg to food borne pathogens; Salmonella spp., Listeria monocytogens, Campylobacter jejuni and Escherichia coli in Shahrekord.

Materials and methods: One hundred normal eggs randomly purchased in the spring and summer of 2008 from small and big supermarkets of Shahrekord, and delivered to the food microbiology lab to be tested. The contents of eggs cultured for those bacteria on selective agar and standard microbiological tests performed to identify the isolated organism.

Results: The result showed that there was no contamination by Salmonella spp., L. monocytogens and C. jejuni in all 100 eggs. However, 19 samples were contaminated by E. coli, four samples by Proteus spp. and one sample by Klebsiella spp. Average colony count of coli form bacteria was 20cfu/g and E. coli was 12/6cfu/g.

Conclusion: We concluded that Salmonella spp., L. monocytogens and C. jejuni contamination of eggs does not make up a serious health hazard in this area. E. coli are known to contaminate the surface of egg while mechanical process can spread the bacteria through eggs.

Significance and impact of the study: It is important to remember that control is required at all levels in the food chain and by separating cooked and raw.