大肠埃希菌O157∶H7家蝇实验带菌消长的研究

摘要/Abstract

摘要：

目的采用大肠埃希菌O157∶H7-EDL933株，实验感染家蝇，观察家蝇体内外感染和带菌消长情况。方法点滴法体外定量染菌，剂量为1 μl(菌悬液浓度为8.0×10⁵～1.9×10⁷ cfu/ml)，并采用昆虫单虫单管方法饲养观察。结果家蝇经体外染菌，获得体内外带菌，体外带菌时间中位数为(96.0±15.3)h(95％CI：66.0～126.0 h)；体内中位数为(144.0±17.3)h(95%CI：110.2～177.8 h)；家蝇体内外带菌消长差异无统计学意义(χ²＝0.74，P＝0.388)，家蝇最长带菌时间至少216 h(9 d)。结论研究结果提示，家蝇不仅是O157∶H7疾病传播的媒介，更重要的可能是人类感染潜在的贮存宿主。

关键词: 大肠埃希菌O157∶H7, 家蝇, 实验感染

Abstract:

Objective To determine the infection status and dynamics in vivo and ex vivo of Escherichia coli O157∶ H7-EDL933 in the infected Musca domestica. Methods In vitro topical application of strains was employed to quantitatively infect the experimental flies, 1 μl apiece (the concentration of bacterial suspension was 8.0×10⁵～1.9×10⁷ cfu/ml). Each fly was bred in one test tube for observation. Results The M. domestica infected In vitro carried the bacteria both in vivo and ex vivo. The median bacteria-carrying duration ex vivo was (96.0±15.3) h (95％CI: 66.0-126.0 h), and the median bacteria-carrying duration in vivo was (144.0 ±17.3) h (95%CI: 110.2-177.8 h). There was no significant difference between the bacteria-carrying dynamics in vivo and ex vivo ( χ²＝0.74，P＝0.388). The longest bacteria-carrying duration of M. domestica was at least 216 h (9 d). Conclusion M. domestica was not only the probable vector of E. coli O157∶H7, but also a potential reservoir host for human infection thereof.

Key words: Escherichia coli O157∶H7, Musca domestica, Experimental infection

中图分类号:

丁华，孙建荣，邱丽华，倪晓平. 大肠埃希菌O157∶H7家蝇实验带菌消长的研究[J]. 中国媒介生物学及控制杂志, 2010, 21(5): 457-459.

DING Hua, SUN Jian-rong, QIU Li-hua, NI Xiao-ping. Dynamics of Escherichia coli O157∶H7 in infected Musca domestica[J]. Chines Journal of Vector Biology and Control, 2010, 21(5): 457-459.

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