Application of pulsed-field gel electrophoresis for tracking source of Salmonella enteritidis in two food poisoning events

Objective To understand the relevance of two food poisoning events, tracking the infectious sources and identifying their transmission routes. Methods A total of 215 samples were collected to conduct pathogen isolation. Biochemical identification and serotyping were performed for the strains isolated and homology analysis was conducted with pulsed-field gel electrophoresis (PFGE). Results A total of 27 strains of Salmonella enteritidis were isolated, in which 4 were from food samples, 3 were from cooks, 20 were from patients. The PFGE patterns of 26 strains were consistent, only 1 was different by 1 strip, the similarity was 96.3%. Conclusion Two food poisoning events were caused by the contamination of S. enteritidis carried by cooks during the preparation of cold dishes. PFGE is suitable for tracking the infectious source and identifying its transmission route in food poisoning event.