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目的:探讨四种基因分型方法在一起F2a志贺氏菌痢暴发的流行病学研究中的意义。方法:对43株分离自患者粪便和食物的菌株分别进行质粒图谱分析、质粒DNA酶切图谱分析、随机PCR分析、setl/set2毒力基因PCR分析.结果:随机PCR将43株F2a志贺氏菌分为西个不同的谱型,质粒图谱、setl/set2毒力基因PCR分为三个不同的谱型。而质粒DNA酶切图谱分为四个不同谱型。其中基因型完全相同的菌株35株,为引起本次菌痢暴发的流行株。7株基因型不同菌株是本次暴发期间同时存在的散发病例。从食物中分离的菌株基因型与流行株相同.证明此次暴发是通过污染的食物而引起传播的。食堂炊事员粪便中虽然分离出了F2a志贺氏菌.但基因型与流行株不同。不是本次暴发的传染源。结论:DNA水平上的分型方法能更为准确、深入地揭示菌痢暴发过程中各分离株之间的流行病学联系。
Objective: To investigate the significance of four genotyping methods in the epidemiological study of Shigella dysenteriae F2a. Methods: Plasmids of 43 strains isolated from the feces and food of patients were analyzed by plasmid, restriction enzyme digestion, random PCR and virulence gene PCR of setl / set2.Results: 43 strains of F2a Shih-Shi The bacteria were divided into three different patterns, plasmid map, setl / set2 virulence genes PCR divided into three different profiles. Plasmid DNA digestion map is divided into four different profiles. Among them, 35 strains of the same genotype were the epidemic strains that caused the outbreak of bacillary dysentery. Seven different strains of genotypes were the co-existing sporadic cases during this outbreak. The genotype of the strain isolated from food was the same as that of the epidemic, proving that the outbreak was caused by contaminated food. Although shiitake F2a was isolated from the excrement of the canteen cook, the genotypes differed from the epidemic strains. Not the source of the outbreak. Conclusion: The typing method at the DNA level can be more accurate and reveal the epidemiological relationship among isolates during the outbreak of bacillary dysentery.