Characterization of Trypanosoma cruzi in southern Ecuador

厄瓜多尔南部克氏锥虫的特征

• 批准号: 7445821
• 负责人: MARIO J GRIJALVA
• 金额: $ 20.18万
• 依托单位: OHIO UNIVERSITY ATHENS
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-05-01 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7445821
• 关键词: Academic Research Enhancement Awards; Address; Affect; Biological; Biological Factors; Biology; Blood; Blood specimen; Chagas Disease; Commerce; Communicable Diseases; Comprehension; Country; DNA Markers; Data; Diagnosis; Ecuador; Environment; Facility Construction Funding Category; Feces; Fever; Gene Frequency; Genes; Genetic; Goals; Habitats; Health; Heart Diseases; Human; Human Activities; In Vitro; Individual; Infection; Knowledge; Latin America; Logistics; Maintenance; Measures; Medical Students; Methods; Microsatellite Repeats; Microscopy; Mini-Exons; Mission; Movement; National Institute of Allergy and Infectious Disease; Parasites; Patients; Phylogenetic Analysis; Play; Polymerase Chain Reaction; Population; Province; Public Health; Regression Analysis; Research; Research Project Grants; Rhodnius; Ribosomal RNA; Role; Rural Community; Sampling; Source; South America; Specific qualifier value; System; Techniques; Testing; Training; Trees; Triatoma; Trypanosoma; Trypanosoma cruzi; United States; base; design; disorder control; improved; knowledge base; migration; prevent; programs; theories; transmission process; vector

DESCRIPTION (provided by applicant): The design of effective country-wide Chagas disease control programs depend on the understanding of the different factors that play a role in the maintenance and transmission of Trypanosoma cruzi. A clear comprehension of the transmission dynamics of this parasite and its relationship to its vector and reservoir species is crucial for the design of control measures aimed at stopping transmission to humans. The predominant T. cruzi vector species in Northern South America occupy both sylvatic and domestic habitats. As sylvatic vectors become domiciliated, blood sources in the peridomestic environment serve as a bridge between the sylvatic and domestic cycles of transmission. Interaction between sylvatic and synanthropic vectors and mammalian reservoirs favors the constant exchange of parasite strains and their transmission to humans. We hypothesize that the T. cruzi II (TCII) lineage will predominate in domestic habitats, and the TCI lineage will become more prevalent as habitats move from domestic to peridomestic to sylvatic habitats. In addition, we also hypothesize that there is high genetic similarity among parasites isolated from different hosts collected in the domestic, peridomestic and sylvatic habitats in Southern Ecuador, indicating frequent parasite exchange. We will test these hypotheses by: (1) molecularly characterizing T. cruzi isolates from different hosts at domestic, peridomestic and sylvatic environments in Southern Ecuador and (2) determining their genetic similarity; (3) Finally, in order to understand the biotic and abiotic factors that influence gene flow between parasite populations, we propose to examine the relationship between genetic distance and geographical distance. To accomplish these aims we will collect triatomines, mammalian reservoirs and human blood in a set of rural communities located in different ecological zones within Loja Province, in Southern Ecuador. We will isolate and molecularly characterize T. cruzi from these sources using PCR amplification of the non-transcribed spacer regions of the mini-exon gene, 24Sa rRNA and 18Sa rRNA. In addition we will determine the genetic flow among parasite populations infecting the different hosts by analyzing up to 11 polymorphic microsatellites loci in conjunction with the construction of phylogenetic trees. Finally, we will use geostatistical techniques to examine the relationship between the genetic and spatial distances of the various T. cruzi isolates. In addition to helping understand the transmission cycles of T. cruzi, this project will provide excellent training opportunities for undergraduate, graduate and medical students while fortifying the PI's research program and strengthening the institutional research environment, thereby fulfilling the goals of Academic Research Enhancement Award (AREA). The results of this project will add to the existing basic biological knowledge base and contribute towards the National Institute of Allergy and Infectious Diseases' (NIAID) mission of understanding and preventing infectious diseases and thus, improving the health of millions of people in the United States and around the world. PUBLIC HEALTH RELEVANCE: Infection with the parasite Trypanosoma cruzi threatens 100 million people in Latin America, and constitutes a major cause of heart disease in this region. The proposed project will examine the transmission cycles of this parasite Southern Ecuador, which is representative of a vast region of South America where the biological factors affecting T. cruzi transmission have been scarcely studied in the past. The proposed research will expand the knowledge regarding the biology of T. cruzi transmission in the Andean region, which is paramount for the establishment of control programs aimed at stopping transmission of the parasite to human populations.

描述（由申请人提供）：有效的全国南美锥虫病控制方案的设计取决于对克氏锥虫维持和传播中起作用的不同因素的理解。清楚地了解这种寄生虫的传播动态及其与病媒和宿主物种的关系，对于设计旨在阻止向人类传播的控制措施至关重要。在南美洲北部，克氏锥虫病媒的主要种类占据森林和家庭栖息地。随着森林病媒的定居，家庭周围环境中的血液来源成为森林和家庭传播周期之间的桥梁。森林和共栖媒介与哺乳动物宿主之间的相互作用有利于寄生虫菌株的不断交换及其向人类的传播。我们假设克氏T. cruzi II （TCII）谱系将在家养生境中占主导地位，并且随着栖息地从家养到家养周围再到森林生境的迁移，TCI谱系将变得更加普遍。此外，我们还假设在厄瓜多尔南部的家庭、家庭周围和森林生境中收集的不同宿主分离的寄生虫具有高度的遗传相似性，表明寄生虫交换频繁。我们将通过以下方法来验证这些假设：(1)在厄瓜多尔南部的家庭、家庭周围和森林环境中对来自不同宿主的克氏锥虫分离株进行分子表征；(2)确定它们的遗传相似性；(3)最后，为了了解影响寄生虫种群间基因流动的生物和非生物因素，我们建议研究遗传距离与地理距离之间的关系。为了实现这些目标，我们将在厄瓜多尔南部洛哈省不同生态区的一组农村社区收集三爪虫、哺乳动物储存库和人类血液。我们将利用PCR扩增迷你外显子基因24Sa rRNA和18Sa rRNA的非转录间隔区，从这些来源分离克氏锥虫并进行分子表征。此外，我们将通过分析多达11个多态性微卫星位点并结合系统发育树的构建来确定感染不同宿主的寄生虫群体之间的遗传流动。最后，我们将使用地质统计学技术来检验各种克氏锥虫分离株的遗传和空间距离之间的关系。除了帮助了解克氏锥虫的传播周期外，该项目还将为本科生、研究生和医学生提供良好的培训机会，同时加强PI的研究计划和加强机构研究环境，从而实现学术研究增强奖（AREA）的目标。该项目的结果将增加现有的基础生物学知识库，并有助于国家过敏和传染病研究所（NIAID）了解和预防传染病的使命，从而改善美国和世界各地数百万人的健康。公共卫生相关性：克氏锥虫感染威胁着拉丁美洲的1亿人，是该区域心脏病的一个主要原因。拟议的项目将检查这种寄生虫在厄瓜多尔南部的传播周期，该地区是南美洲广大地区的代表，过去很少对影响克氏锥虫传播的生物因素进行研究。拟议的研究将扩大关于安第斯地区克氏锥虫传播生物学的知识，这对于建立旨在阻止该寄生虫向人类传播的控制规划至关重要。

项目成果

Influence of ecological factors on the presence of a triatomine species associated with the arboreal habitat of a host of Trypanosoma cruzi.

生态因素对与克氏锥虫宿主树栖栖息地相关的锥蝽物种存在的影响。

• DOI: 10.1186/s13071-018-3138-4
• 发表时间: 2018
• 期刊: Parasites & vectors
• 影响因子: 3.2
• 作者: Ocaña-Mayorga,Sofía;Lobos,SimónE;Crespo-Pérez,Verónica;Villacís,AnitaG;Pinto,CMiguel;Grijalva,MarioJ
• 通讯作者: Grijalva,MarioJ

Comprehensive Survey of Domiciliary Triatomine Species Capable of Transmitting Chagas Disease in Southern Ecuador.

• DOI: 10.1371/journal.pntd.0004142
• 发表时间: 2015
• 期刊: PLoS neglected tropical diseases
• 影响因子: 3.8
• 作者: Grijalva MJ;Villacis AG;Ocaña-Mayorga S;Yumiseva CA;Moncayo AL;Baus EG
• 通讯作者: Baus EG

Colonization and genetic diversification processes of Leishmania infantum in the Americas.

• DOI: 10.1038/s42003-021-01658-5
• 发表时间: 2021-01-29
• 期刊: Communications biology
• 影响因子: 5.9
• 作者: Schwabl P;Boité MC;Bussotti G;Jacobs A;Andersson B;Moreira O;Freitas-Mesquita AL;Meyer-Fernandes JR;Telleria EL;Traub-Csekö Y;Vaselek S;Leštinová T;Volf P;Morgado FN;Porrozzi R;Llewellyn M;Späth GF;Cupolillo E
• 通讯作者: Cupolillo E

Molecular data supports monophyly of Triatoma dispar complex within genus Triatoma.

分子数据支持锥蝽属内锥蝽复合体的单系性。

• DOI: 10.1016/j.meegid.2020.104429
• 发表时间: 2020
• 期刊: Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases
• 作者: Santillán-Guayasamín,Soledad;Barnabé,Christian;Magallón-Gastelum,Ezequiel;Waleckx,Etienne;Yumiseva,CésarA;Grijalva,MarioJ;Villacís,AnitaG;Brenière,SimoneFrédérique
• 通讯作者: Brenière,SimoneFrédérique

Chagas vectors Panstrongylus chinai (Del Ponte, 1929) and Panstrongylus howardi (Neiva, 1911): chromatic forms or true species?

• DOI: 10.1186/s13071-020-04097-z
• 发表时间: 2020-05
• 期刊: Parasites & Vectors
• 影响因子: 3.2
• 作者: A. Villacís;J. Dujardin;F. Panzera;C. Yumiseva;S. Pita;Soledad Santillán-Guayasamín;Marco I. Orozco;Katherine D. Mosquera;M. Grijalva