Zhang Hongzhi, Dou Xin, Shi Tianqi, Xu Biyao, Liu Yangtai, Zhang Yinghua, Song Xia, Liang Yingying, Yu Ying, Chen Min, Dong Qingli, Wu Huanyu
Shanghai municipal center for disease control and prevention, Shanghai 200336, China.
School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
Int J Food Microbiol. 2025 Oct 2;441:111323. doi: 10.1016/j.ijfoodmicro.2025.111323. Epub 2025 Jun 17.
Listeria monocytogenes poses a major global food safety concern as a widespread pathogen causing listeriosis. In this study, a total of 553 L. monocytogenes isolates across 9 food types sampled during 2020-2023 in Shanghai, the largest city in China, and among the largest metropolitan areas worldwide, were identified using whole-genome sequencing (WGS). The association among clonal complexes (CCs) and food matrices was determined using an Apriori algorithm approach. Results revealed that less virulent CC9 and CC121 isolates without LIPI-2-4 were the predominant strains frequently detected, showing strong association with pork, beef, lamb, chicken, and processed meat products, suggesting their widespread presence in various meat types. Virulent CC8 without LIPI-2-4 was predominantly found in processed meat products, cooked meat products, and clinical cases. More virulent CC87 with LIPI-4 was frequently detected in clinical cases and chicken. Similarly, CC2 with LIPI-3 showed a strong association with seafood products. Therefore, the observed CCs aligned with previously defined virulence classes, offering valuable data for microbiological risk assessment. Further research is necessary to explore unique CCs in China and the virulence profiles. Nevertheless, this study highlights the insufficiency of relying solely on LIPI-1-4 for determining L. monocytogenes pathogenicity. Notably, the presence of inlA PMSC mutations revealed the distribution of virulence potential of L. monocytogenes, which might be helpful to improve risk assessment approaches. Furthermore, incorporating CCs into L. monocytogenes surveillance may aid in tracing contamination sources and monitoring transmission patterns, offering insights for risk assessment.
单核细胞增生李斯特菌作为一种导致李斯特菌病的广泛传播的病原体,是全球主要的食品安全问题。在本研究中,使用全基因组测序(WGS)对2020年至2023年期间在中国最大城市上海(也是全球最大的都市区之一)采集的9种食品类型中的553株单核细胞增生李斯特菌分离株进行了鉴定。使用Apriori算法方法确定克隆复合体(CCs)与食品基质之间的关联。结果显示,无毒力的CC9和CC121分离株(无LIPI-2-4)是经常检测到的优势菌株,与猪肉、牛肉、羊肉、鸡肉和加工肉制品有很强的关联,表明它们在各种肉类类型中广泛存在。无毒力的CC8(无LIPI-2-4)主要存在于加工肉制品、熟肉制品和临床病例中。毒力更强的带有LIPI-4的CC87在临床病例和鸡肉中经常被检测到。同样地,带有LIPI-3的CC2与海产品有很强的关联。因此,观察到的CCs与先前定义的毒力类别一致,为微生物风险评估提供了有价值的数据。有必要进一步研究中国独特的CCs及其毒力谱。然而,本研究强调了仅依靠LIPI-1-4来确定单核细胞增生李斯特菌致病性的不足。值得注意的是,inlA PMSC突变的存在揭示了单核细胞增生李斯特菌毒力潜力的分布,这可能有助于改进风险评估方法。此外,将CCs纳入单核细胞增生李斯特菌监测可能有助于追踪污染源和监测传播模式,为风险评估提供见解。