Epidemiological and Whole Genome Sequencing Analysis of Restaurant Salmonella Enteritidis Outbreak Associated with an Infected Food Handler in Jiangxi Province, China, 2023.
Silu Peng, Huomei Xiong, Jun Lu, Fei Luo, Chengwei Liu, Houde Zhou, Wei Tong, Zhilu Xia, Daofeng Liu
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引用次数: 0
Abstract
In China, Salmonella is one of the most frequent causes of bacterial gastroenteritis, and food handlers in restaurants as an important contaminated source were rarely reported. In May 2023, an outbreak of Salmonella enterica serovar Enteritidis infection in a restaurant in Jiangxi Province, China, was investigated. Cases were interviewed. Stool samples from cases, anal swabs from restaurant employees, suspicious raw food materials, and semifinished food were collected and examined. Pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS) were performed to determine the relatedness of the pathogen isolates. Antimicrobial resistance genes and virulence genes of isolates were analyzed by WGS. The antimicrobial profile of the isolates was detected by broth microdilution, which involved 20 different antibiotics. Among the 31 patrons, 26 showed gastrointestinal symptoms. Five Salmonella Enteritidis strains were isolated from patients (2), semifinished food (2), and food handler (1). The results of PFGE and single-nucleotide polymorphism showed that these five isolates were identical clones. These findings demonstrated that this outbreak was a restaurant Salmonella Enteritidis outbreak associated with an infected food handler. The rates of resistance to nalidixic acid and colistin and intermediate resistance to ciprofloxacin were 100%, 80%, and 100%, respectively. These outbreak isolates harbored point mutation gyrA p.D87G. The cause of inconsistency between the genotype and phenotype of resistance was deeply discussed. A total of 107 virulence genes were found in each isolate, with many being associated with Salmonella pathogenicity island (SPI)-1 and SPI-2. As an overlooked contamination source, infected food handlers can easily cause large-scale outbreaks. This outbreak highlighted that the government should enhance the training and supervision of food hygiene and safety for food handlers to prevent foodborne outbreaks.
期刊介绍:
Foodborne Pathogens and Disease is one of the most inclusive scientific publications on the many disciplines that contribute to food safety. Spanning an array of issues from "farm-to-fork," the Journal bridges the gap between science and policy to reduce the burden of foodborne illness worldwide.
Foodborne Pathogens and Disease coverage includes:
Agroterrorism
Safety of organically grown and genetically modified foods
Emerging pathogens
Emergence of drug resistance
Methods and technology for rapid and accurate detection
Strategies to destroy or control foodborne pathogens
Novel strategies for the prevention and control of plant and animal diseases that impact food safety
Biosecurity issues and the implications of new regulatory guidelines
Impact of changing lifestyles and consumer demands on food safety.