Investigation of Salmonella food poisoning using pulsed-field gel electrophoresis

Objective:To apply pulsed-field gel electrophoresis(PFGE)to investigating trace infection sources and genotype of Salmonella strains isolated from food poisoning.Methods:Salmonella strains were analyzed by pulsed-field gel electrophoresis with restriction enzyme Xbal.The similarity coefficient of PFGE patterns were calculated using Band based/Dice assay.Results:PFGE patterns of strains from the same outbreak of food poisoning were identical.Through Band based/Dice assay the similarity coefficient is more than or equal to 0.96.The PFGE pattern of strain isolated from cake store was different from that of strain isolated from certain institute.Conclusion:The food poisoning is induced by the cutting tool and butter in cake shop.Then the food poisoning was induced by Beijing chicken roll in a certain institute.The above results indicated that two strains isolated from two institutes may be having the same source.PFGE is a stabile,reliable assay having high resolution ability for trace infection sources.PFGE plays important roles for investigating trace infection sources in Salmonella food poisoning.