Zhang Peipei, Essendoubi Saida, Keenliside Julia, Reuter Tim, Stanford Kim, King Robin, Lu Patricia, Yang Xianqin
Agriculture and Agri-Food Canada, Lacombe, Alberta, Canada.
Alberta Agriculture and Forestry, Edmonton, Alberta, Canada.
NPJ Sci Food. 2021 Jul 1;5(1):15. doi: 10.1038/s41538-021-00097-0.
Three E. coli O157:H7 outbreaks have been attributed to contaminated pork in Alberta, Canada, recently. This study investigates the phylogenetic relatedness of E. coli O157:H7 from pigs, cattle, and pork-production environments for source attribution. Limited strain diversity was observed using five conventional subtyping methods, with most or all strains being in one subgroup. Whole-genome single nucleotide polymorphism analysis confirmed the recent ancestry of the isolates from all three sources. Most environmental isolates clustered closer with pig isolates than cattle isolates. Also, a direct link was observed between 2018-outbreak environmental isolates and isolates collected from a pig farm in 2018. The majority of pig isolates harbor only one Shiga toxin gene, stx, while 70% (35/50) of the cattle isolates have both stx and stx. The results show some E. coli O157:H7 strains could establish persistence on pig farms and as such, pigs can be a significant source of the organism.
最近，加拿大艾伯塔省发生的三起大肠杆菌O157:H7疫情被归因于受污染的猪肉。本研究调查了来自猪、牛和猪肉生产环境的大肠杆菌O157:H7的系统发育相关性，以进行源头追溯。使用五种传统分型方法观察到菌株多样性有限，大多数或所有菌株都属于一个亚组。全基因组单核苷酸多态性分析证实了所有三种来源的分离株的近期祖先。大多数环境分离株与猪分离株的聚类比与牛分离株更紧密。此外，观察到2018年疫情环境分离株与2018年从一个养猪场收集的分离株之间存在直接联系。大多数猪分离株仅携带一个志贺毒素基因stx，而70%（35/50）的牛分离株同时具有stx和stx。结果表明，一些大肠杆菌O157:H7菌株可以在养猪场持续存在，因此，猪可能是该生物体的重要来源。
