关于鼠疫自然疫源地判定依据与面积估算的探讨

An Approach to the Foundations for Confirming Existance of Natural Foci of Plague and It’s Areas Estimation

本文回顾了我国鼠疫自然疫源地的判定规定。简介了新疆疫源地的判定与面积估算。指出了我国北方疫源地大片大片地分布在显域生境的草原、草甸草原、荒漠草原上；而南方大绒鼠一齐氏姬鼠（Ｅ．ｍｉｌｅｔｕｓ—Ａ．ｃｈｅｖｒｉｅｒｉ）疫源地则呈树枝状存在于隐域生境山谷灌丛之内，而不是大片大片地分布在显域生境针阔叶林与云南松林带之中。对疫源地判定与疫源地面积估算进行了讨论。然后，提出了疫源地判定的三项主要依据与二项次要依据。主要依据：１．从主要宿主动物分布区内的主要宿主动物或媒介昆虫中分离出强毒鼠疫菌；２．主要宿主动物密度（新疆可定为二种旱獭，Ｍ．ｂａｉｂａｃｉｎａ、Ｍ．ｃａｕｄａｔａ、Ｍ．ｈｉｍａｌａｙａｎａ均在１公顷０．５只以上；定点法，长尾黄鼠Ｃ．ｕｎｄｕｌａｔｕｓ在１公顷２只以上）；３．主要媒介蚤的宿主体表指数（新疆可定为上述三种旱獭的Ｏ．ｓｉｌａｎｔｉｅｗｉ在１以上，长尾黄鼠的（Ｃ．ｔｅｓｑｕｏｒｕｍ在４以上）。作者还建议，如在已判定的疫源地毗连周围继续扩大调查，并其结果符合下列二项次要依据时，亦可判定扩大调查区为疫源地。次要依据：１．在扩大调查区内查出动物的鼠疫血清学阳性结果；２．主要宿主动物群落覆盖度（新疆可定为?

n this paper,there were a backward glance at natural foci of plague in China and a brief introduction to the confirmation as well as areas asessment of natural foci in Xinjiang. The wide tracts of northern foci in Chi- na distribute on the dominant habitat, such as prairie,pelouse prairie and desert steppe,wihile the E. miletus-A. chevrieri Foci in the south of China couldn’t be found in the coniferous forest and Yunnan pine forest of dominant habitat but exist in the mountain valley and shrub of non- dominant habitat as arborization。 The con-firmation and assessment of the natural foci were also discussed in the paper。 Further more, three principal foundations and two minor bases of foci confirming were raised.The main foundations are that:1. Virulent Y. pestis isolated from the principal host animals and vector insects in the areas of principal host animals. . Den- sity of main host animals(3 kinds of marmota were determined in Xinjiang, all M. baibacina,M. caudata and M. himalayana were more than0.5/ha, Fixed-spot Method,C. undulatus is more than 2/ha ). 3. Body surface index of the principal vector fleas(the index of O. silantiewi on 3 kinds of marmota mentioned above is more than l,and that of C. tesquorum on C. undulatus more than4). The author suggested that the extanded inves-tigation area, be confirmed as focus if the enlarged survey had been continued in the area bordering on the con-firmed foci,and its results accorded with the 2 secondary foundations as follow. The secondaryfoundations are that:. Positive serological results of plague found in animals in the enlarged investigation districts.2. The overlay degree of animal community of principal host(3 kinds of marmota and C. undulatus are all over 35% in Xinjiang). Finally,ranges of investigation areas and discovered foci were pointed out,and the area could be estimated according to the ranges.