[Epidemics and risk factors of plague in Junggar Basin, Xinjiang Uygur Autonomous Region, 2007-2016]

Zhonghua Liu Xing Bing Xue Za Zhi. 2017 Oct 10;38(10):1394-1398. doi: 10.3760/cma.j.issn.0254-6450.2017.10.020.
[Article in Chinese]

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/hm(2) to 22.6/hm(2) respectively. However, the spatial distribution appeared asymmetrical, with the highest seen in Kelamayi and Wumuqi-midong counties, as 14.2/hm(2) and 13.0/hm(2) 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 of R. 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 of R. 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.

目的: 了解准噶尔盆地鼠疫自然疫源地鼠疫流行现状。 方法: 采用数理统计方法分析2007-2016年在该疫源地18个县(市、区)采集的鼠疫宿主动物、媒介及鼠疫抗体和病原体检测数据。 结果: 该疫源地大沙鼠密度在时间分布上呈波动状态,为2.1~22.6只/hm(2);空间分布呈不均匀分布,以克拉玛依市和乌鲁木齐市米东区最高,分别为14.2只/hm(2)和13.0只/hm(2);夜行鼠捕获率为4.2~10.1只/100夹次,以2014年最高,为10.1只/100夹次;子午沙鼠为优势种(81.9%);大沙鼠染蚤率和总蚤指数空间和时间分布存在波动,平均染蚤率为90.7%,总蚤指数为10.44,簇鬃客蚤为优势种,分布最广,占总蚤指数的47.8%;夜行鼠平均染蚤率为20.2%,总蚤指数为1.20,以同形客蚤指名亚种和秃病蚤指名亚种为优势种类;鼠疫血清学检测啮齿动物13种9 087份,阳性617份。其中大沙鼠阳性率最高(9.4%),其次为三趾毛脚跳鼠(1.1%)。空间分布存在2个鼠疫流行强度较高区域:昌吉至木垒的准噶尔东部区域,以克拉玛依、沙湾和乌苏甘家湖为中心的中部地区,大沙鼠鼠疫抗体阳性率分别为14.3%和13.6%。时间分布上呈波动状态:2008年为低谷,2013年呈高峰,阳性率分别为1.0%和19.3%;10年间共计检出鼠疫菌18株,以大沙鼠及其体蚤检菌最多。以乌鲁木齐市米东区、吉木萨尔和克拉玛依市检菌最多。 结论: 准噶尔盆地鼠疫自然疫源地是一个物种组成丰富、宿主和媒介群落结构多样、鼠疫流行强度不断变化的复杂生态系统,动物间鼠疫流行呈全区域性、连续性和异质性,存在主动和被动接触感染2类3种鼠疫风险播散链。.

Keywords: Animal plague; Junggar Basin; Prevalence; Risk factor.

MeSH terms

  • Animals
  • China / epidemiology
  • Flea Infestations / epidemiology*
  • Gerbillinae* / microbiology
  • Humans
  • Insect Vectors
  • Mice
  • Plague / epidemiology*
  • Risk Factors
  • Rodent Diseases
  • Siphonaptera / microbiology
  • Yersinia pestis / immunology
  • Yersinia pestis / pathogenicity