近日，来自英属哥伦比亚大学的研究人员在温哥华地下通道所卖的鱼制品中发现了利斯塔氏菌属（listeria）的细菌的行踪，研究人员Kevin Allen检测了40个样品，并从7个大型连锁超市、10个零售商那里买来了烟熏鱼（smoked tuna）、加糖的鲑鱼（candied salmon）以及鱼肉干（fish jerke），用这些来进行他们的研究。
研究人员的这项研究成果刊登在了近日的杂志Food Microbiology上，文章中研究者表示，在这些速食鱼肉制品中，至少含有20%的listeria菌，而且至少有5%都是有致病性的。研究者表示，尽管listeria菌的标准达到了规定，但是在储存或者处理的过程中，这些细菌可以进行繁殖，Allen表示，在处理这些速食食品的时候，比如切割、称重、包装等，有可能会增加细菌交叉污染的概率，高温可以杀死listeria菌，但是很多人在食用鱼肉速食之前并不会加工一下。Allen还补充到，尤其是对孕妇、老年人以及免疫力低下的病人来说，食用这种含有listeria菌的速食品增加了他们的健康风险。
研究者同时又检测了在温哥华地下通道所买的速食肉类，他们没有在速食肉食品（包括红肠、咸牛肉等）中发现listeria菌，如果每千克速食品中超过100个listeruia菌体，这就违反了食品安全规定，如果人们食用了不合规定的食品不仅仅会引起呕吐，甚至痢疾，利斯特菌病的感染也会导致大脑和血液的感染，甚至引起死亡。
（生物谷：T.Shen编译）
doi:10.1016/j.fm.2011.12.015
PMC:
PMID:
Occurrence and characterization of Listeria spp. in ready-to-eat retail foods from Vancouver, British Columbia
Jovana Kovačević, Lili R. Mesak, Kevin J. Allen,
The occurrence of Listeria spp. and Listeria monocytogenes in retail RTE meat and fish products in Vancouver, British Columbia (B.C.) was investigated. To assess potential consumer health risk, recovered L. monocytogenes isolates were subjected to genotypic and phenotypic characterization. Conventional methods were used to recover Listeria spp. from deli meat (n = 40) and fish (n = 40) samples collected from 17 stores. Listeria spp. were recovered only from fish samples (20%); 5% harboured Listeria innocua, 5% had L. monocytogenes and 10% contained Listeria welshimeri. L. monocytogenes isolates serotyped as 1/2a and 1/2b, possessed dissimilar PFGE patterns, and had full-length InlA. Three 1/2a clonal isolates encoded the 50 kb genomic island, LGI1. Antimicrobial resistance (AMR) profiling showed all Listeria spp. possessed resistance to cefoxitin and nalidixic acid. L. monocytogenes were resistant to clindamycin, two were resistant to streptomycin, and one to amikacin. Reduced susceptibility to ciprofloxacin was seen in all L. monocytogenes, L. innocua and three L. welshimeri isolates. Reduced susceptibility to amikacin and chloramphenicol was also observed in one L. monocytogenes and three L. welshimeri isolates, respectively. Recovery of L. monocytogenes in fish samples possessing AMR, full-length InlA, LGI1, and serotypes frequently associated with listeriosis suggest B.C. consumers are exposed to high-risk strains.
