ABSTRACT
Objective To explore the epidemic situation of animal plague in Junggar Basin natural plague foci.Methods Data on epidemics of plague and on population involved,as well as results on antibodies and pathogens,were analyzed.Samples on animals and vectors were collected from 18 counties in Junggar Basin plague natural foci between 2007 and 2016.Results The density of Rhombomys (R.) opimus was temporally fluctuant,from 2.1/hm2 to 22.6/hm2 respectively.However,the spatial distribution appeared asymmetrical,with the highest seen in Kelamayi and Wumuqimidong counties,as 14.2/hm2 and 13.0/hrn2 respectively.Rates of capture on nocturnal rodents were from 4.2％ to 10.1％,with the highest rate as 10.1％ in 2014.Meriones meridianus appeared the dominant species in the nocturnal community of rodents,which accounted for 81.9％.Regarding the spatial and temporal distributions,rates ofR.opimus with fleas appeared fluctuant,with an average rate as 90.7％ and the average total flea index was 10.44.In flea community of R.opimus,Xenopsylla (X.)skrjabini was found the dominant species,popular in distribution and accounted for 47.8％.The average rate of nocturnal rodents with flea was 20.2％,with total flea index as 1.20 and the dominant fleas were X.conformis conformis and Nosopsyllus laeviceps.A total of 13 species with 9 087 serum samples from rodents were detected as having Y.pestis antibody by IHA,with 617 positive samples.Of them,the positive rate of having R.opimus appeared the highest (9.4％),followed by D.sagitta (1.1％).Spatially,two clustered areas were found,with one in the eastern Junggar Basin from Changji to Mulei county,with the antibody positive rates ofR.opimus as 14.3％.The other one was in the central area of Junggar Basin,including Kelamayi,Shawan and Wusu counties,with the antibody positive rate as 13.6％.The prevalence of plague on R.opimus was fluctuant,with the lowest seen in 2008,with the average antibody positive rate of R.opimus as 1.0％ and the highest as 19.3％ in 2013.A total of 18 strains were isolated from 2007 to 2016.However,most of the strains were isolated from R.opimus and parasitic fleas,accounted for 8/9,in Kelamayi,Wulumuqi-midong and Jimusaer,respectively.Conclusions Complex ecosystem was seen in the Junggar Basin natural plague foci,with the multiple composition of species and different community structure of hosts and vectors,plus the flustering prevalence.Animal plague was seen in the whole region with succession of the plague nature foci.Passive transmission of plague between human beings and animals through close contacts was seen which was driven by economic benefits to some degree.
ABSTRACT
Objective To explore the epidemic situation of animal plague in Junggar Basin natural plague foci.Methods Data on epidemics of plague and on population involved,as well as results on antibodies and pathogens,were analyzed.Samples on animals and vectors were collected from 18 counties in Junggar Basin plague natural foci between 2007 and 2016.Results The density of Rhombomys (R.) opimus was temporally fluctuant,from 2.1/hm2 to 22.6/hm2 respectively.However,the spatial distribution appeared asymmetrical,with the highest seen in Kelamayi and Wumuqimidong counties,as 14.2/hm2 and 13.0/hrn2 respectively.Rates of capture on nocturnal rodents were from 4.2％ to 10.1％,with the highest rate as 10.1％ in 2014.Meriones meridianus appeared the dominant species in the nocturnal community of rodents,which accounted for 81.9％.Regarding the spatial and temporal distributions,rates ofR.opimus with fleas appeared fluctuant,with an average rate as 90.7％ and the average total flea index was 10.44.In flea community of R.opimus,Xenopsylla (X.)skrjabini was found the dominant species,popular in distribution and accounted for 47.8％.The average rate of nocturnal rodents with flea was 20.2％,with total flea index as 1.20 and the dominant fleas were X.conformis conformis and Nosopsyllus laeviceps.A total of 13 species with 9 087 serum samples from rodents were detected as having Y.pestis antibody by IHA,with 617 positive samples.Of them,the positive rate of having R.opimus appeared the highest (9.4％),followed by D.sagitta (1.1％).Spatially,two clustered areas were found,with one in the eastern Junggar Basin from Changji to Mulei county,with the antibody positive rates ofR.opimus as 14.3％.The other one was in the central area of Junggar Basin,including Kelamayi,Shawan and Wusu counties,with the antibody positive rate as 13.6％.The prevalence of plague on R.opimus was fluctuant,with the lowest seen in 2008,with the average antibody positive rate of R.opimus as 1.0％ and the highest as 19.3％ in 2013.A total of 18 strains were isolated from 2007 to 2016.However,most of the strains were isolated from R.opimus and parasitic fleas,accounted for 8/9,in Kelamayi,Wulumuqi-midong and Jimusaer,respectively.Conclusions Complex ecosystem was seen in the Junggar Basin natural plague foci,with the multiple composition of species and different community structure of hosts and vectors,plus the flustering prevalence.Animal plague was seen in the whole region with succession of the plague nature foci.Passive transmission of plague between human beings and animals through close contacts was seen which was driven by economic benefits to some degree.
ABSTRACT
Objective To investigate the type of plasmid map of Y. pestis in the R. opimas natural plague loci in Junggar Basin. Methods A total of 39 plasmid DNA of Y. pestis which were isolated from the natural plague loci of Junggar Basin, Tianshan Mountain, Kunlun Mountain, Qinghai-Tibet Plateau and In-ner Mongolia were extracted by the methods of Kado and Liu. The plasmid map was analyzed by the methods of agarose gel eleetrophoretogram. Results Two types of plasmid map were found in 26 Y. pestis which were isolated from Junggar Basin. Of them 23 were 6 × 106, 45 × 106 and 65 × 106 type of plasmid map, and 3 were 6 × 106, 45 × 106 and 72 × 106 type. Conclusion There are two types of plasmid map in the R. opi-mus natural plague loci in Junggar Basin. One type, which is the dominant type in this area, is 6 × 106, 45 × 106 and 65 × 106 type. This type is also similar to the dominant plasmid map type of the nature plague loci of Tianshan Mountain, Kunlun Mountain, Qinghai-Tibet Plateau and Inner Mongolia. The other type is 6 × 106, 45 × 106 and 72 × 106 type, and this type is new plasmid map type of Y. pestis in our country.
ABSTRACT
Objective To compare different fragment profiles of Yersinia pestis isolated from Rhombomys opimus plague natural focus in the Junggar Basin for determining their genomovars newly found in China.Methods Chromosomal DNA of Yersinia pestis Was extracted with routine method.DFR analysis was performed as reported previously.Results The different fragment profiles of Yersinia pestis from Rhombomys opimus plague natural focus is absence of DFR01,04,06,07,10,13 and DFR 15-18.It is a novel genomovar of Yersinia pestis in China,which is different from Yersinia pestis from the other plague natural foci.Conclusion The genomovar of Yersinia pestis from Rhombomys opimus plague natural focus in the Junggar Basin is a novel one in China.