基于地理信息系统的青海省鼠疫菌毒力研究

目的测定青海省鼠疫自然疫源地鼠疫菌毒力，建立青海省鼠疫自然疫源地毒力基础数据。方法选取392株鼠疫菌进行毒力试验，用SPSS18．0计算各试验菌株的半数致死量（LD50），运用地方病地理信息系统分析其空间构成。结果392株鼠疫菌中鼠疫强毒株有367株，占93．62％；鼠疫中等毒力株有10株，占2．55％；鼠疫低毒株有10株，占2．55％；鼠疫弱毒株有5株，占1．27％；发现青海省鼠疫自然疫源地祁连山型菌株毒力比青藏高原型菌株毒力强。结论青海省鼠疫自然疫源地鼠疫菌以鼠疫强毒株为主。

Virulence research for Yersinia pestis based on Geographic Information System

The aim of this study is to determine the virulence of Yersinia pestis strains in Qinghai plague foci so as to es- tablish virulence underlying data for Qinghai plague foci. A total of 392 Yersinia pestis strains were selected to carry out strain virulence test. Median lethal dose （LD50） of these strains was calculated by SPSS18.0, and the spatial compositions were ana- lyzed by Geographic Information System. Result showed that among 392 Yersinia pestis strains, there were 367 velogenic strains which accounted for 93.62%, 10 moderate virulence strains which accounted for 2.55 %, 10 low virulence strains which accounted for 2.55%, and 5 hypovirulent strains which accounted for 1.27%. We found that the Qilian Mountain genotype strains had stronger virulence than the Qingzang Plateau genotype strains in Qinghai plague loci. In conclusion, the velogenic strains might constitute a large proportion in Yersinia pestis strains in Qinghai plague foci.