云南玉龙及古城区鼠疫自然疫源地判定及初步研究

目的确定云南玉龙县及古城区鼠疫自然疫源地的存在,提出防控策略。方法采用常规调查方法,通过血清学、细菌学、基因诊断等技术进行判定。结果共分离到5株鼠疫杆菌,均酵解甘油、麦芽糖、阿胶糖,不酵解鼠李糖、密二糖,脱氮试验阳性。均带有Pgm 、PstI 、FI 、Vwa 等毒力决定因子;疫区犬血清阳性率为23.5%;猫血清阳性率为26.7%。结论细菌学证实玉龙县为鼠疫自然疫源地,目前鼠疫流行处于活跃期;血清学证实古城区为新的鼠疫疫源区(县);阳性血清动物分布面积210km2,并有进一步扩散趋势;齐氏姬鼠及大绒鼠是本地区优势鼠种,玉龙绒鼠有局部分布。特新蚤指明亚种,方叶栉眼蚤为优势蚤种;分离的鼠疫菌与滇西纵谷型及滇闽居民区型菌株生化特性不同,与西藏北部青藏高原型鼠疫菌的生化特性接近。

Confirmation and study of Plague Natural Foci for Yulong County and Guchengqu in Yunnan Province

Objective To ascertain plague natural foci in Yulong county and Guchengqu,Yunnan province and provide strategies for plague control and prevention.Methods Routine investigation methods were applied in this research.Plague natural foci was confirmed using techniques of serology,bacteriology and gene diagnosis.Results Five Yersina pestis strains with virulence factors of Pgm ,PstI ,FI ,and Vwa were obtained.Five strains can ferment Glycerol,Maltose,and Arabinose,but cannot ferment Rhamnose and Melibiose.The deamination test of 5 strains were positive.For plague serology test in natural foci,the positive rate of dogs were 23.5%,the positive rate of cats were 26.7%.Conclusions Yulong county is confirmed as plague natural foci via bacteriology test and plague epidemic is activing currently.Guchengqu is confirmed as a county of new plague natural foci via serology test.The distribution area for animal of positive serology test is about 210 km2.and has trend of further spread.Apodemus chevriert and Eothenomys miletus are predominant rat species in this natural foci.Distribution of Eothenomys in Yulong county is localization.Neopsylla specialis specialis and Ctenophthalmus quadratus are predominant flea species.The biological characters of 5 Y.pestis strains are different from the biological characters of Y.pestis strains from Western Yunnan Transverse Valley Type and Yunnan and Fujian Residential Area Type,but are similar with the biological characters of Y.pestis strains from Qinghai and Tibet Plateau Type located in north Tibet.