青海省德令哈市鼠疫病原学及流行病学特征分析

Etiological and epidemiological study of plague in Delingha,Qinghai Province

目的探讨青海省德令哈市鼠疫菌株生物学特点及流行病学意义,为该地区的鼠疫防治提供科学依据。方法对1995-2014年青海省德令哈市分离的33株鼠疫菌株进行生化试验、毒力测定、毒力因子鉴定、鼠疫菌差异片段(Different Region,DFR)分型等研究。结果 33株被试菌株生物型为古典型、生态型均为青藏高原型,菌株基因型为8型29株(占87.88%),44型2株,1b型1株,5型1株,主要基因组型为8型;被试菌株中81.82%(27/33)的鼠疫菌4个毒力因子俱全;毒力检测结果显示所有被测菌株的鼠疫菌均为强毒株。结论青海省德令哈市分离的鼠疫菌具备青藏高原鼠疫病原体特性,鼠疫菌的毒力强;该地区的鼠疫防治工作不容忽视。

Objective To discuss the biological characteristics and epidemiological significance of Yersinia pestis strains isolated in Delingha,Qinghai Province,to provide a scientific basis for plague prevention and control. Methods Thirtythree Y.pestis strains isolated in Delingha,Qinghai Province from 1995-2014 were studied.Strains were subjected to biochemical testing and toxicity testing,their virulence factors were identified,and strains were subjected to different region（DFR）typing. Results All of the strains were of the antique biovar and of the Qinghai-Tibetan Plateau ecotype.Twenty-nine strains were genotyped as genomovar 8（87.88%）,2were genotyped as genomovar 44,1was genotyped as genomovar 1b,and 1was genotyped as genomovar 5;the main genotype of Y.pestis was genomovar 8.Of all strains,81.8%（27/33）contained all four virulence factors.Toxicity testing indicated that all of the strains were velogenic.Conclusion The strains isolated in Delingha,Qinghai Province had the characteristics of the plague pathogen Y.pestis from the Qinghai-Tibetan plateau.Y.pestisis highly virulent,so plague prevention and control efforts in this area cannot be ignored.