云南省梁河县家鼠鼠疫疫源地中致病性耶尔森菌的调查

Investigation on pathogenic Yersinia in the plague foci of domestic rats in Lianghe County of Yunnan Province

目的对梁河县家鼠鼠疫疫源地鼠疫、假结核及小肠结肠炎3种致病性耶尔森菌分布情况调查分析并研究其病原学特征。方法选择梁河县5个鼠疫常规监测的乡镇,采集鼠盲肠标本,4℃冷增菌后采用耶尔森菌选择培养基进行致病性耶尔森菌的分离;对所分菌株进行生化鉴定、生物分型、血清分型和毒力基因(ail、yst A、yst B、yad A、vir F及rbfc)检测。结果共捕鼠533只,主要是黄胸鼠、臭鼩鼱、斯氏家鼠等;自鼠肠道中分离到2株小肠结肠炎耶尔森菌,分离率为0.4%(2/533),皆分离自黄胸鼠;2株小肠结肠炎耶尔森菌均为生物1A型,且毒力基因检测均为阴性;未检测到鼠疫耶尔森菌和假结核耶尔森菌。结论梁河县家鼠中少量携带非致病性小肠结肠炎耶尔森菌,未发现鼠疫耶尔森菌与假结核耶尔森菌的相关线索。

Objective To investigate the distribution of pathogenic Yersinia in the plague foci of domestic rats in Lianghe County and to study its etiological characteristics.Methods Five townships in the routine monitoring of plague in Lianghe County were selected.The rat cecal specimens were collected and incubated at 4℃,Yersinia selective medium was used to isolate pathogenic Yersinia.Biochemical identification,Bio-typing,serotyping and virulence gene(ail,yst A,yst B,yad A,vir F and rbfc)detection of the strains were carried out.Results A total of 533 rats were collected from five townships in Lianghe County,included Rattus flavipectus,Suncus murinus,Rattus sladerni and so on.Two strains of Yersinia enterocolitica were isolated,with the isolation rate of 0.4%(2/533).They were all isolated from Rattus flavipectus.The biotypes of the 2 Yersinia enterocolitica were all 1 A type.The virulence genes of the 2 strains were negative.No Yersinia pestis and Yersinia pseudotuberculosis were detected.Conclusion A small number of rodents in Lianghe County carried non-pathogenic Yersinia enterocolitica,but no clues related to Yersinia pestis and Yersinia pseudotuberculosis were found.