NATURAL HISTORY OF BABESIOSIS

血液寄生虫巴贝斯虫和莱姆螺旋体 伯氏巴氏杆菌病和白纹伊蚊都是由鹿硬蜱传播的。 迷你(也称为肩周炎)，并在以下区域传播 目前流行莱姆病。在人类中，感染这两种病毒 生物体可以单独出现，也可以组合出现，最初的预期是 研究表明，持续感染伯氏杆菌和 细小支原体可因合并感染而增强。神秘莫测 微小巴贝斯虫感染是地方性血库特别关注的问题 地区，因为无症状的献血者感染了 原生动物与许多输血获得性病例有关 该国现已发生一例输血感染病例，新发病例为 描述了美国西部类似巴贝西亚的支原体(WAI)。 令人惊讶的是，人们对Babesial的自然历史知之甚少 感染。这里列举的具体目标旨在定义 进一步研究巴贝斯虫病在人和小鼠急性和慢性巴贝斯虫病模型中的病程 我们正在研究的慢性感染。首先，由于大多数梨形体种 迄今为止的研究包括慢性携带者状态，作为其 传输周期，我们将尝试记录慢性携带者状态 在人类身上，并通过使用分子和 免疫学方法。第二，我们动物和人类通过构建基因 来自松果体特异基因组DNA的表达文库，其次是 反应血清文库的免疫学筛选。这会有帮助的 美国将鉴定在体内表达的贝贝斯蛋白并将定义 更精确地检测支原体感染期间的血清学反应。 在第三个目标中，我们将发展和评估小鼠感染模型。 并特别强调小鼠品系对鹦鹉热体的敏感性 感染。最后，在第四个目标中，我们将评估潜在的 巴贝斯虫感染小鼠模型的免疫抑制特性。 Burgdorferi和B.microti混合感染。通过这些工具获得的信息 研究将最终导致对自然的更好的理解 感染巴贝斯虫的病史及其对人类构成的风险 这种新出现的病原体。

The blood parasite Babesia microti and the spirochetal agent of Lyme disease, B. burgdorferi, are both transmitted by the deer tick, Ixodes dammini ( also called I. scapularis) and are transmitted in areas that are currently endemic for Lyme disease. In humans, infection with these two organisms may occur alone or in combination, and initial prospective studies suggest that persistence of infection with B. burgdorferi and the B. microti piroplasm may be enhanced by concurrent infection. Cryptic Babesia microti infection is of special concern to blood banks in endemic areas, since asymptomatic blood donors harboring infection with the protozoan have been implicated in many transfusion-acquired cases in this country, and one transfusion-acquired case has now occurred with the newly described Babesia-like piroplasm (WAI) in the western United States. Surprisingly little is known about the natural history of babesial infection. The specific aims enumerated here are oriented toward defining further the course of babesiosis in humans and in mouse models of acute and chronic infection that we are studying. First, since most piroplasm species studied to date comprise a chronic carrier state as part of their transmission cycle, we will attempt to document the chronic carrier state in humans, and to monitor the course of infection by using molecular and immunologic methods. Second, we animals and humans by constructing genetic expression libraries from piroplasm-specific genomic DNA, followed by immunologic screening of the libraries with reactive sera. This will help us to identify babesial proteins that are expressed in vivo and will define with greater precision the serologic responses during piroplasm infection. In the third aim, we will develop and evaluate mouse models of infection with a special emphasis on mouse strain susceptibility to piroplasm infection. Finally, in the fourth aim, we will evaluate the potential immunosuppressive properties of babesial infection in a mouse model of B. burgdorferi and B. microti coinfection. The information gained by these studies will lead ultimately to a better understanding of the natural history of babesial infection and the risks posed to humans infected with this emerging pathogen.