Epidemiological investigation and analysis of an outbreak of foodborne disease caused by Vibrio parahaemolyticus

ObjectiveAn epidemiological investigation and analysis were conducted on an outbreak of food-borne disease to explore the patterns of occurrence， the critical points of on-site management and countermeasures for food-borne disease outbreaks， providing a basis for future management of similar incidents and prevention and control strategies.MethodsEpidemiological characteristics of the foodborne disease outbreak among diners at Restaurant W between 24-27 May 2021， were analyzed using descriptive epidemiological methods； A case-control study was conducted to investigate suspected foods， and an environmental hygiene investigation was performed to trace the contamination process of the suspected foods； The 40 biological samples from patients and food handlers at Restaurant W， along with the 18 food samples and samples from the food processing environment， were collected for testing.ResultsThis incident revealed 344 individuals affected， with 96 cases， representing the incidence rate of 27.90%； Vibrio parahaemolyticus was detected in 31 of the 58 samples collected， with a detection rate of 53.45%. The pulsed field gel electrophoresis patterns of the strains isolated from beef and the cases were identical， confirming the presence of Vibrio parahaemolyticus contamination in the beef served as food.ConclusionThis incident represents an outbreak of foodborne disease at W Restaurant， attributed to the consumption of beef contaminated with Vibrio parahaemolyticus. Prompt sealing of the site and the collection of samples for testing were crucial in controlling the spread of the disease and identifying the source and route of contamination. It is imperative to enhance coordination among various departments， cultivate and enhance capabilities for grassroots’s departments of disease prevention and control .