丽江市动物感染致病耶尔森菌调查及其病原学研究

Investigation and etiological study of animals infected with pathogenic Yersiniain the City of Lijiang

目的调查丽江部分地区鼠和犬感染致病耶尔森菌情况,了解其病原学特征,为该地耶尔森菌病的防治提供依据。方法在丽江古城区和玉龙县的19个自然村51个点采集野鼠结盲肠标本1 220份,犬肛门拭子标本531份,对其进行致病耶尔森菌的分离培养、生化鉴定以及相关毒力基因检测。结果 foxA基因93份,耶尔森菌初筛总阳性率5.31%;假结核耶尔森菌及鼠疫耶尔森菌检测均阴性。生化鉴定阳性菌株35份,阳性率为2.17%。生物血清型1A/O:9型6株,1A/血清未定型24株,非1A/血清未定型2株,3/O:3型2株,1A/O:3型1株。毒力基因检测分为3种型别,其中ail^-、ystA^-、ystB^+、yadA^-、virF^-、rbfc^- 4株,ail^+、ystA^+、ystB^-、yadA^+、virF^+、rbfc^+ 2株,ail^-、ystA^-、ystB^-、yadA^-、virF^-、rbfc^- 29株。结论丽江市玉龙县和古城区鼠、犬存在小肠结肠炎耶尔森菌感染,分离菌包含3个生物型和3种血清型及3种毒力基因型。未检出假结核耶尔森菌及鼠疫耶尔森菌。可为当地防治提供参考。

Objectives To investigate the distribution and etiology of pathogenic Yersinia among mice and dogs in some parts of Lijiang and to provide evidence for the local CDC to prevent and control pathogenic Yersinia. Methods A total of 1 220 cecum samples were collected from field mice in 51 villages in the Old Town District of Lijiang and Yulong County,and 531 anal swabs samples from dogs were used to isolate and culture pathogenic Yersinia.Virulence genes were biochemically identified and detected. Results In total,93 samples tested positive for the foxA gene at a rate of 5.31%.None of the samples tested positive for Y.pseudotuberculosis or Y.pestis.Strains were biochemically identified in 35 samples at a rate of 2.17%.Strains included bio/serotype 1A/O：9（6 strains）,biotype 1A with an unknown serotype（24 strains）,non-biotype 1A with an unknown serotype（2 strains）,bio/serotype3/O：3（2 strains）,and bio/serotype 1A/O：3（1 strains）.Three patterns of virulence genes were identified.Four strains had ystB（ail^＋,ystA^＋,ystB^-,yadA^＋,virF^＋,and rbfc^-）,2 strains had ail,ystA,yadA,virF,and rbfc（ail^＋,ystA^＋,ystB^-,yadA^＋,virF^＋,and rbfc^＋）,and 29 strains had none of the tested genes（ail^-,ystA^-,ystB^-,yadA^-,virF^-,and rbfc^-）.Conclusion Mice and dogs in the Old Town District of Lijiang and Yulong County were infected with Y.enterocolitica.The identified strains included 3 biotypes and 3 serotypes and 3 patterns of virulence genes.Y.pseudotuberculosis and Y.pestis were not detected.These findings can provide evidence for the local CDC to prevent and control pathogenic Yersinia.