Factors In Emergence of New Sleeping Sickness Foci In Uganda

描述（由申请人提供）：乌干达是非洲唯一存在两种形式的非洲人类锥虫病（HAT）的国家；西北地区有慢性冈比亚病，东南部有急性罗得西亚病。最近有报告称，HAT从东南部的传统疫源地扩大到乌干达中部以前没有疾病的新地区。鉴于两种疾病在诊断和治疗方面的差异，乌干达中部两种疾病带可能合并将造成一场重大的公共卫生危机。这次FIRCA将调查导致乌干达中部最近疾病疫源地扩大的因素，以便能够实施有效的控制方法。拟议的研究建立在亲本基金（NIAID R01Al068932）的研究结果的基础上，该基金分别研究了乌干达罗得西亚和冈比亚疫源地的fuscipes （Gff）的分子生态学和进化遗传学。亲本资助结果表明，西北部冈比亚疫源地的采采蝇种群与东南部罗得西亚疫源地的采采蝇种群在遗传上高度分化。在这里，我们将调查从历史上存在HAT疫源地的东南部地区扩展的Gff蝇是否传播目前在乌干达中部出现的罗得西亚病。此外，我们将调查第二种病媒物种——白僵蝗——的存在是否可能通过加强HAT的动物宿主而助长罗得西亚病流行的维持。这项调查的结果将立即与乌干达正在进行的病媒控制规划相关。这一建议还将在乌干达托罗罗的国家牲畜资源研究所促进HAT流行病学理论和实验方法方面的重大能力建设，大部分工作将在该研究所进行。

DESCRIPTION (provided by applicant): Uganda is the only country in Africa where both forms of the Human African Trypanosomiasis (HAT) disease exist; chronic gambiense disease in the northwest and acute rhodesiense disease in the southeast. Recent expansions of HAT from the traditional foci in the southeast to new territories in central Uganda, which previously were disease-free, have recently been reported. Possible merger of the two disease belts in central Uganda would create a major public health crisis given the differences in diagnostics and treatment associated with the two forms of disease. This FIRCA will investigate the factors contributing to the recent expansion of disease foci in central Uganda so that effective control methods can be implemented. The proposed studies build on the findings of the Parent Grant (NIAID R01Al068932), which addresses the molecular ecology and evolutionary genetics aspect of Glossina f. fuscipes (Gff) in the rhodesiense and gambiense foci in Uganda, respectively. Parent grant results have shown that tsetse populations in the gambiense foci in the northwest are genetically highly differentiated from the rhodesiense foci in the SE. Here we will investigate whether Gff flies expanding from southeast areas, where historical HAT foci exist, transmit rhodesiense disease now emerging in central Uganda. In addition, we will investigate whether the presence of a second vector species, Glossina pallidipes, may be fueling the maintenance of rhodesiense epidemics by enhancing the animal reservoirs of HAT. Results from this investigation will immediately be relevant for the ongoing vector control program in Uganda. This proposal will also result in significant capacity building both in theory and experimental methods on HAT epidemiology at National Livestock Resources Institute in Tororo Uganda, where the majority of the work will be performed. PUBLIC HEALTH RELEVANCE: Human sleeping sickness transmitted by tsetse is a fatal disease in sub-Sahara; HAT has reemerged in south-eastern Uganda since late 1980s. Expansion of disease into new foci in previously disease free areas of central Uganda is alarming. Studies proposed here will investigate HAT emergence and specifically will focus on fly movements and tsetse species distribution as potential factors to understand disease epidemiology in Uganda.