2000～2009年新疆山地鼠疫自然疫源地动物鼠疫疫情形势分析

目的总结分析近10年来新疆山地鼠疫自然疫源地动物鼠疫流行状况,研判预测未来之流行趋势。方法对2000～2009年新疆山地鼠疫疫源地内各监测单位动物鼠疫监测资料进行汇总分析。结果新疆山地鼠疫疫源地仍然保持原有的四大类型山地鼠疫疫源地,疫源地共涉及新疆18个县（市）,面积约167000km^2。在此期间,新增温泉县鼠疫疫源县,新增疫源地面积4000km^2,主要宿主、媒介和病原体的生化性状与北天山西段相同,属北天山灰旱獭—长尾黄鼠鼠疫疫源地的组成部分。10年间,新疆四大类型山地鼠疫自然疫源地43个县（市）次分离鼠疫菌357株,年均有4.8个县次发生动物鼠疫流行,67个县次检出鼠疫宿主动物阳性血清674份,年均7.4个县次有动物鼠疫疫情。其中,天山灰旱獭—长尾黄鼠疫源地的宿主动物和媒介种群数量一直维持一个比较高的密度水平,种群结构稳定,动物间鼠疫流行呈现时间上的连续性,年均4.3个县次分离出鼠疫菌,占4块疫源地总和的89.6%,鼠疫菌分离数占总计的98.6%,年均5.3个县次检出宿主鼠疫阳性血清,占四大类型疫源地年均阳性县次总数的71.6%,阳性血清数占86.8%。新疆南部的南天山、帕米尔高原和昆仑山鼠疫疫源地的宿主媒介指标低于北天山山地,染蚤率和蚤指数仅分别为42.5%、48.8%、33.2%和1.9、2.5、1.2。此3块疫源地年均分离出鼠疫菌的县次分别为0.2、0.1和0.1个县次,分别占全疆的4.7%、2.3%和2.3%,分离出的鼠疫菌数分别占全疆的0.56%、0.28%和0.56%。3块疫源地年均检出宿主动物的鼠疫阳性血清的县次数分别为0.6、0.2和0.2,血清阳性率分别为0.62%、0.3%和0.66%。结论新疆天山北坡鼠疫疫源地动物间鼠疫呈现出稳定、持续、且流行较为猛烈的状态,南天山、帕米尔和昆仑山鼠疫自然疫源地呈现相对较弱的动物鼠疫流行状态,但疫源地宿主和媒介组成稳定,鼠疫疫源地的疫源性依然存在,在局部范围内仍存在动物间鼠疫流行。

Analysis of epidemic situation of animal plague in mountainous plague natural foci in Xinjiang from 2000 to 2009

Objective To summarize and analyze epidemic situation of animal plague in mountainous plague natural foci in Xinjiang in recent 10 years, and to research and predict prevalent tendency in future. Methods Surveillance data of animal plague by monitoring units in mountainous plague natural foci in Xinjiang from 2000 to 2009 were collected and analyzed. Results Mountainous plague natural foci in Xinjiang remained the original 4 types, involving 18 counties （cities） with area of 167 000 km^2. During the period, there was a new plague focus in Wenquan County with the area of 4 000 km^2. Biochemical characteristics of principal host, vector and pathogen were as same as those in the western part of Northern Tianshan, belonging to component of Northern Tianshan plague foci of Marmota baibacian-Citellus undulatus. In the 10 years, there were totally 357 strains of Yersinia pestis isolated from 43 counties （cities） in the 4 mountainous plague natural foci, with animal plague prevalence in 4.8 counties-times on average annually. 67 counties-times were detected for 647 serum samples of host animals of the positive, and there were 7.4 counties-times with plague prevalence in animal. Meanwhile, amount of host animals and vectors in the foci kept a high density with stable population structure. Plague in animals showed time continuity. There were 4.3 counties-times with isolation of Y. pestis on average annually, accounted for 89.6%of the total of the 4 foci. The isolated strains occupied 98.6% of the total. Annually, positive sera were detected in 5.3 counties-times on average, holding 71.6% of the total positive counties of the 4 types on average annually, with positive sera accounting for 86.8%. Plague in animals displayed stability and continuity and violent prevalence. Indices of hosts and vectors in southern Tianshan Mountain, Pamirs and Kunlun Mountain were obviously less than those in Northern Tianshan Mountain. Rate of fleas infection and flea index were only 42.5%, 48.8%, 33.2% and 1.9, 2.5, 1.2. The counties-times isolated Y. pestis from these 3 foci were 0.2, 0.1 and 0.1, respectively, accounted for 4.7%, 2.3% and 2.3% of the whole Xinjiang, while the isolated strains occupied 0.56%, 0.28% and 0.56%, separately. The counties-times detected for positive sera of host animals on average annually in these 3 foci were 0.6, 0.2 and 0.2, with positive rate of sera of 0.62%, 0.3% and 0.66%, respectively.