Taxonomy and Epidemiological Importance of Divergent Chagas Disease Vector Taxa

描述(申请人提供)：恰加斯病是拉丁美洲最严重的寄生虫病，也是导致心脏病的主要原因。在中美洲和墨西哥一直很难控制这种寄生虫，因为传播这种寄生虫的主要昆虫种类是在森林和房屋周围地区发现的，而且很容易在熏蒸后重新定居房屋。此外，尽管T.dimidiata标本在它们的地理范围内看起来很相似，但初步数据表明，该物种可能包括不同的分类群。这项研究的长期目标是了解环境和遗传相互作用对恰加斯病传播的影响。作为第一步，将确定中美洲恰加斯病的主要传播媒介--二叠红三角菌种群的分类地位。分类学多样性可以通过几种方式表现出来并影响疾病传播。我们的重点是了解形态变异的程度；染色体DNA序列和组织的多样性；以及来自不同地理位置和一系列生态栖息地的双毛虫种群之间的流行病学差异(血源、毛滴虫感染、首选栖息地)。这项研究的结果将指明遗传上不同的分类群之间的分界线，并将确定最有可能将恰加遗传给人类的分类群。由于我们的一名合作者与危地马拉卫生部和世卫组织中美洲防治恰加斯病倡议密切合作，所获得的信息将立即用于控制工作。此外，通过这项工作，我们将培训来自美国和地方性国家的本科生，以增强公共部门、学术界和工业界所需的科学队伍。与公共卫生相关的恰加斯病是导致心脏病的主要原因，也是拉丁美洲最严重的寄生虫病。为了帮助阻止这种疾病的传播，我们将研究在中美洲传播恰加斯的主要昆虫媒介的遗传学。这将使我们能够确定哪些昆虫种群是该地区查加斯病毒传播的罪魁祸首，并针对这些昆虫开展控制工作。

DESCRIPTION (provided by applicant): Chagas disease is the most serious parasitic disease and a leading cause of heart disease in Latin America. It has been difficult to control in Central America and Mexico since the main species of insect that spreads the parasite, Triatoma dimidiata, is found in forests and as well as areas surrounding houses and readily re-colonizes houses after fumigation. In addition, although T. dimidiata specimens look similar across their geographic range, preliminary data suggest the species may include distinct taxa. The long-term goal of this research is to understand the influence of environmental and genetic interactions on the transmission of Chagas disease. As the first step, the taxonomic status of Triatoma dimidiata populations, the main Chagas disease vector in Central America, will be determined. Taxonomic diversity can manifest itself and affect disease transmission in several ways. We focus on understanding the degree of morphological variation; diversity in the sequence and organization of DNA in chromosomes; and epidemiological differentiation (blood source, T. cruzi infection, preferred habitat) among T. dimidiata populations from distinct geographical localities and across a range of ecological habitats. The results of this research will indicate the dividing lines among genetically distinct taxa, and will identify the taxa most likely to transmit Chagas to humans. As one of our collaborators works closely with the Guatemalan Ministry of Health and the WHO Central American Initiative against Chagas disease, the information obtained will be put immediately to use into the control efforts. In addition, through this work we will train undergraduate students from the U.S. and endemic countries to enhance the scientific workforce needed by the public sector, academia and industry. PUBLIC HEALTH RELEVANCE Chagas disease is a leading cause of heart disease and the most serious parasitic disease in Latin America. To help halt transmission of this disease, we will study the genetics of the main insect vector that transmits Chagas in Central America. This will allow us to identify which populations of insects are responsible for most of the Chagas transmission in this region and develop control efforts targeting these insects.