丽江野鼠鼠疫自然疫源地10年扩散趋势研究

A 10-year study of plague natural foci diffusion trend in Lijiang

目的通过更大范围内的自然疫源地调查,研究丽江野鼠鼠疫自然疫源地分布范围的变化扩散趋势,探讨其规律,为鼠疫防治工作提供科学依据。方法采用鼠疫间接血凝试验(IHA)检测鼠疫指示动物和鼠类血清中鼠疫F1抗体。结果通过近10年三轮更大范围内的系统性调查提示:自然疫源地的自然环境复杂,分布范围逐渐演变,由小而大,扩散速度较快,扩散趋势呈现一定的规律性,即由最初发现证实的面积大约210km^2,3个乡镇9个行政村35个自然村,逐步以黄山镇南溪村委会鹿子村为中心向周边扩散,2013年增加约250km^2,达到450km^2,阳性点覆盖面积增加了119.0%。2015年进一步扩散增加约180km^2,达到630km^2,阳性点覆盖面积再新增40.0%,累计调查明确的疫源地分布于玉龙、古城两县(区)的8个乡镇、14个行政村、65个村民小组。扩散方向以向东向北扩散为主,向北扩散趋势更为明显,致使疫源地中心点向东北方向偏移,即中心点不再是黄山镇南溪村委会的鹿子村,而是北移至太安乡吉子村委会汝南化,并有进一步扩散的趋势。尽管疫源地累计发现了7次鼠间鼠疫流行并成功处置,但历次疫源地调查中,区域危险人群、鼠血清、搜索的自毙动物、小型兽类等调查采集的标本均未检测到阳性信息。结论指示动物血清学证实,疫源地范围已经明显向北向东移,以向东北方向扩散为主。扩散趋势明显,扩散速度较快,疫情扩散的风险进一步增高。

Objective To investigate the plague natural foci distribution changes in Lijiang.Methods Plague indirect hemagglutination test(IH A)was used to detect the F1antibody in serum of indicator animals and rodents.Results In the past10years,through3rounds of extensive and systemic survey,we found that the natural environment of natural foci was complex,the distribution range developed faster and faster,and the diffusion trend presented certain regularity.Plague was initially confirmed in an area of210km2,involving3towns of9administrative villages and35natural villages,gradually spreading from Lvzi Village in Huangshan County to the adjacent villages,from250km2in2013to630km2in2015,and the positive coverage increased by159.0%.Conclusion Indicator animal serological findings confirmed that foci range has been spreading from the north to the east,especially to the northeast.The diffusion rate is faster,and there is an increased risk of plague.