ADAPTATION OF LEISHMANIA TO NATURAL DIETS OF THE VECTOR

利什曼原虫生活在媒介白蝇的消化道中， 由苍蝇的食物和消化酶混合而成。我们会 确定食物成分的变化是否会影响 病原体的发展过程以及这些因素是否会影响 自然的传播力。 一系列的实验将会把各种自然的 发生的食用植物和蜜露，在约旦谷发现，与 帕帕塔西肺炎衣原体主要感染病程。首先，这些食物将是 提供给实验室饲养的受感染苍蝇以及每种饲料的效果 以估计寄生虫密度、死亡率和形态为特征的 肠道内容物染色制剂中的阿伯丁。推论出的标准 这些实验将被用来筛选可能的野外饮食 它们对媒介苍蝇自然感染的影响。那么，我们将 通过以下方式评估这些食物在自然界中被摄取的频率 检查野生苍蝇的内脏。利什曼狂症的流行将 与特定食物来源的存在相关。 配套的一系列实验将调查血液中 约旦谷特有的不同动物影响着 沙蝇的感染。因此，我们将确定利什曼人是否 感染在受感染的苍蝇进食后减少或消除 特别是自然产生的动物。因为中肠蛋白分解在 媒介白蝇在不同种类的宿主和主要宿主之间存在差异 利什曼原虫的糖偶联物影响这些消化酶，我们 比对取食后沙蝇体内分泌的类胰酶 在这个主机阵列上。 建议将饮食分析作为影响病媒的一个因素 媒介能力和利什曼传播力构成了 利什曼病流行病学的新方法。我们期待着 这些结果将有助于对矢量的基本理解-- 病原体之间的相互作用，并可能提供有用的方法来控制 这些感染。

Leishmania resides in the alimentary tract of vector sandflies, in a medium comprising the food of the fly mixed with digestive enzymes. We shall determine whether variations in the composition of the food influence the course of development of the pathogen and whether such factor may affect the natural force of transmission. One series of experiments will correlate the presence of various naturally occurring food plants and honeydew, found in the Jordan Valley, with the course of L. major infection in P. papatasi. First, these foods will be provided to laboratory-reared infected flies and the effect of each diet characterized by estimating parasite density, mortality and morphological abberations, in stained preparations of gut-contents. The criteria deduced from these experiments will be used to screen putative field diets for their effect on natural infections in vector flies. Then, we shall evaluate how frequently each of these foods are ingested in nature, by examining the guts of wild-caught flies. The prevalence of Leishmania will be correlated with the presence of particular food sources. A companion series of experiments will investigate whether blood of different animals, endemic to the Jordan Valley, affects the course of infection in sandflies. Thus, we shall determine whether leishmanial infection is diminished or eliminated after infected flies feed on particular naturally occurring animals. Because midgut proteolysis in vector sandflies varies between different kinds of hosts and the major glycoconjugates of the Leishmania influences these digestive enzymes, we shall compare the trypsin-like enzymes secreted in sandflies after feeding on this array of hosts. The proposed analysis of the diet of the vector as a factor that affects vector competence and the force of leishmanial transmission constitutes a novel approach to the epidemiology of the leishmaniases. We anticipate that these results will contribute to a basic understanding of vector- pathogen interactions and may provide methods useful in the control of these infections.