福氏2a志贺氏菌肠毒素基因分型

Gena types of Shigella enterotoxins of S.flexneri 2a

目的 对福氏 2a志贺氏菌 (Shigellaflexneri 2a ,F2a)的志贺氏肠毒素 1(Shigellaenterotoxin 1,SET1)和志贺氏肠毒素 2 (Shigellaenterotoxin 2 ,SET2 )进行基因分型 ,提高菌痢暴发流行时同源性分析的水平。方法 对一起暴发F2a菌痢在现场流行病学调查的基础上 ,用聚合酶链反应 (PCR)方法 ,检测 43株F2a菌的志贺氏肠毒素 1基因 (set 1)和志贺氏肠毒素 2基因 (set 2 ) ,进行基因分型和同源性鉴定。结果 43株F2a菌株分为 3种基因型 ,即 1株set 1( - ) /set 2 ( +) ;3株set 1( +) /set 2 ( - ) ;39株set 1( +) /set 2 ( +)。结论 本次菌痢暴发是经污染食物传播 ,暴发事件中夹杂着散发病例 ,set 1/set

Objective To identify homogenous clones of S.flexneri 2a, using gene distribution polymorphism of Shigella enterotoxin 1(set 1) and Shigella enterotoxin 2(set 2) in a Shigellosis outbreak caused by S.flexneri 2a. Methods In addition to field epidemiological investigation,43 strains of S.flexneri 2a were determined by polymerase chain reaction(PCR). Results The 43 strains (1 from food, 1 from a carrier, 41 from patients) were divided into 3 clones(set1+/set2+ for 39 strains, set1-/set2+ for 1,set1+/set2- for 3 strains). Conclusion This outbreak was caused by S.flexneri 2a. The route of transmission was contaminatedfood borne. Some sporadic cases were noticed during the outbreak. The method used in this study was satisfactory to the identification of S.flexneri 2a.