Genetyping And Epidemiology Analysis Of Mongolian Gerbil Yersinia Pestis In Hebei

Plague is a re-emerging natural focal disease, Plague primary existes in rodents and can cause human pandemic,with the highly contagious, spread fast, mortality rate. Plague is categorized as a Class A infectious disease, the most serious category under China’s Law on the Prevention and Treatment of Infectious Diseases, China is a country with most widely distributed , most complicated, and most active natural plague foci in world, at least 12 types of natural plague foci still exist, covering 299 counties in 17 provinces , and plague among animals is still prevalent in several regions. Plague in Hebei province belongs to the Inner Mongolia Plateau Meriones unguiculatus plague foci, where historily, plague had caused large scale of prevalence. From the seventies of the 20th century, there had been existed a total of 4 animal plague outbreaks in Hebei Province,and more than 100 strains of Yersinia pestis were isolated from Hebei Plague focus.。for the reason that the Heibei plague focus is adjacient to Beijing, the illustration about Yersinia pestis genetic characteristics in Heibei has very important significance for the disease control and prevention.In this study, the genetic characteristics of plague bacteria in Hebei province were studied using three genotyping methods. i.e.Differential fragments (DFR) research with the 23 fragments and clustered regularly interspaced short palindromic repeats (CRISPR)and Multiple-locus numbers tandem repeat analysis (MLVA) with 26 VNTR loci scheme. cluster analysis was carried out using the bionumerics software.DFR analysis results showed that the plague strain of Hebei province belonged to Genomovaru genetype. CRISPR results showed that the plague isolates of Hebei province were divided into 2 genotypes, Cb2 and a new genetype.The results of DFR and CRISPR were consistent with the conventional biological typing.MLVA provided more detailed polymorphism among strains isolated in Hebei province, and generally could be divided into 2 clusters with 5 subtypes.