2018—2019年辽宁省副溶血性弧菌临床和食品分离株分子流行病学分析

Molecular epidemiological analysis of food and clinical isolates of Vibrio parahaemolyticus in Liaoning Province in 2018-2019

目的了解辽宁省副溶血性弧菌(Vibrio Parahaemolyticus,VP)的流行特征,为辽宁省食源性疾病的防控和应急事件的处置提供可靠的技术支持。方法对2018—2019年辽宁省301株临床和食品VP分离株进行血清学分型、脉冲场凝胶电泳(PFGE)分型、毒力基因(tlh、tdh、trh)鉴定及耐药试验。结果除了59株VP分离株不能进行血清学分型外,其他分离株共分为17个血清型,血清型以O3群、O1群和O2群为主。血清型O3与O1群分离株相似度高。PFGE主要分成11组优势带型,A-K组,其中A-G组为主要流行致病分子型。临床分离株毒力基因携带情况主要为tlh+、tdh+、trh-,食品分离株毒力基因携带情况主要为tlh+、tdh-、trh-。VP分离株主要对β-内酰胺类(CFZ和AMP)、大环内酯类抗菌药物(ERY)耐药。即食食品分离株耐药率远高于非即食食品分离株。结论由于即食食品的特殊性和来自于国外的特性,这些菌株具有引起食源性疾病暴发流行的高风险,应高度重视。部分食品分离株也具有引起食源性疾病的风险,应给予关注。相关部门除了应加强对国内海产品及其抗菌药物使用管控外,更应加强对进口海产品的监管。

This study was aimed at understanding the epidemic characteristics of Vibrio parahaemolyticus(VP)in Liaoning Province,to provide reliable technical support for the prevention and control of foodborne diseases and emergency responses in Liaoning Province.A total of 301 clinical and food VP isolates from Liaoning Province between 2018 and 2019 were subjected to serotyping pulsed field gel electrophoresis(PFGE)typing,virulence gene(tlh,tdh,and trh)identification,and drug resistance testing.All isolates,except for 59 VP isolates that could not be serotyped,were divided into 17 serotypes.The O3 group,O1 group,and O2 group were the main serotypes.The similarity between serotype O3 and O1 group isolates was high.PFGE divided the isolates into 11 dominant bands in groups A-K.Groups A-G were the main epidemic pathogenic molecular type.The virulence genes in clinical isolates were primarily tlh+,tdh+,and trh-,whereas the virulence genes in food isolates were primarily tlh+,tdh-,and trh-.VP isolates showedβ-resistance to lactams(CFZ and AMP)and macrolide antibiotics(ERY).The drug resistance rate in instant food isolates was much higher than that in non-instant-food isolates.Because of the characteristics of non-cooked ready-to-eat foods and food from foreign sources,the isolated strains had a high risk of causing foodborne disease outbreaks and should be highly valued.Some food isolates also pose a risk of foodborne diseases and therefore warrant attention.In addition to strengthening control of the use of domestic seafood and antibacterial drugs,supervision of imported seafood should also be strengthened by relevant departments.