摘要目的:分析内蒙古高原长爪沙鼠疫源地动物间鼠疫流行规律，并找出影响鼠疫流行的关键因素，为鼠疫预测预警及风险评估提供理论依据。方法:选取内蒙古高原长爪沙鼠疫源地乌兰察布高原片区19个旗（县、市、区）的长爪沙鼠密度、长爪沙鼠体蚤指数、鼠疫流行强度等鼠疫监测数据，结合温度、降水、厄尔尼诺活动（南方涛动指数，SOI）等环境数据，使用相关分析、结构方程模型、等级关联等方法，分析疫源地内动物间鼠疫流行规律及关键因素。结果:内蒙古高原长爪沙鼠疫源地的鼠疫流行周期多为5~10年。相关分析中，各研究因素相互间均有影响。结构方程模型筛选出鼠疫流行的主要影响因素为SOI、长爪沙鼠密度和温度，SOI对鼠疫流行强度（-0.022）和温度（-0.029）有负作用，长爪沙鼠密度对鼠疫流行强度有正作用（0.014），温度对鼠疫流行强度有负作用（-0.065）。等级关联中，长爪沙鼠密度处于高值时，当年鼠疫流行强度为高的概率为4/9；当SOI处于低值时，当年鼠疫流行强度为高的概率为5/9；当温度处于低值时，当年鼠疫流行强度为高的概率为5/9。当年鼠疫流行强度处于高值时，次年鼠疫流行强度为高的概率为5/8；当年长爪沙鼠密度处于高值时，次年鼠疫流行强度为高的概率为4/9；当年SOI处于低值时，次年鼠疫流行强度为高的概率为4/9。结论:气候和生物因素均可影响鼠疫的暴发流行，如果出现厄尔尼诺现象、温度偏低、长爪沙鼠密度和上一年鼠疫流行强度偏高等情况，应提前采取应对措施，防范鼠疫的暴发和流行。

abstractsObjective:To analyze the epidemic situation of plague among animals in the foci of Meriones unguiculatus in Inner Mongolia Plateau, and to find out key influencing factors affecting the epidemic of the plague, and to provide theoretical basis for the prediction, early warning and risk assessment of the plague. Methods:The monitoring data including gerbils density, gerbils body flea index, plague epidemic intensity, etc., as well as environmental data including temperature, precipitation and El Ni?o activity (Southern Oscillation Index, SOI) from 19 banners (counties, cities and districts) in Ulanqab Plateau area, the foci of Meriones unguiculatus in Inner Mongolia Plateau were selected. The methods of correlation analysis, structural equation model and rank correlation were used to analyze the epidemic and key influencing factors of plague among animals in the foci. Results:The plague epidemic cycle in the foci of Meriones unguiculatus in Inner Mongolia Plateau was 5 to 10 years. The correlation analysis results showed that all the factors had influence on each other. Structural equation model screened out that the main influencing factors of plague epidemic were SOI, gerbils density and temperature. SOI had a negative effect on plague epidemic intensity (-0.022) and temperature (-0.029), while gerbils density had a positive effect on plague epidemic intensity (0.014), and temperature had a negative effect on plague epidemic intensity (-0.065). In rank correlation, when the gerbils density was at a high value, the probability of high plague epidemic intensity in that year was 4/9; when SOI was at a low value, the probability was 5/9; when the temperature was at a low value, the probability was 5/9. When the plague epidemic intensity was at a high value in that year, the probability of the plague epidemic intensity being high in the following year was 5/8; when the gerbils density was at a high value in that year, the probability was 4/9; when SOI was at a low value in that year, the probability was 4/9. Conclusion:Climate and biological factors can affect prevalence of plague, and countermeasures should be taken in advance to prevent plague outbreaks when El Ni?o phenomenon, low temperature, high density of gerbils, and high previous-year prevalence of plague appear.