Malaria Vector Population Genetic Division and Vector Competence in Hainan Island

项目概述疟疾是东南亚大湄公河次区域国家面临的重大公共卫生问题和社会经济发展的障碍。该地区疟疾流行病学的巨大地理异质性与不同的病媒系统和不同的寄生虫病媒能力有关。作为疟疾控制战略的主要措施，经杀虫剂处理的蚊帐和室内喷雾剂已导致对拟除虫菊酯类杀虫剂产生抗药性，并极大地改变了蚊子群落和种群结构。在中国海南岛，广泛使用杀虫剂控制疟疾，导致中国和东南亚的主要疟疾病媒小按蚊（Anopheles minimi蚊）最初急剧减少，最近又出现反弹。杀虫剂驱动的媒介种群演替不仅重构了媒介群落，而且恢复后的蚊虫种群也表现出改变的叮咬偏好。基于这些观察结果，我们假设近年来强化的疟疾病媒控制措施和农业害虫控制措施造成了海南岛疟疾病媒的明显生态物种演代和种群遗传瓶颈。因此，本FIRCA提案旨在利用海南岛地理隔离的优势，阐明主要疟疾媒介在杀虫剂控制下的演变。我们将确定不同生态型的An。来自丘陵和平原地区的小蚊对恶性疟原虫感染的媒介能力不同。该研究将为预测东南亚其他疟疾流行地区基于杀虫剂的蚊虫控制措施对蚊子进化的响应提供宝贵信息。拟开展的研究将培养1名来自疫区国家的博士研究生和1名博士后，有助于研究能力建设。该项目将主要在中国重庆师范大学与陈斌博士合作进行，作为NIH拨款U19 AI089672的延伸。

DESCRIPTION (provided by applicant): Malaria Vector Population Genetic Division and Vector Competence in Hainan Island Project Summary Malaria is a significant public health problem and impediment to socioeconomic development in countries of the Greater Mekong Subregion of Southeast Asia. The tremendous geographical heterogeneity of malaria epidemiology in this region is associated with diverse vector systems with different vectorial capacities for the parasites. As the major measures of malaria control strategies, insecticide-treated bed nets and indoor sprays have resulted in pyrethroid resistance, and greatly reshaped the mosquito community and population structures. In Hainan Island of China, extensive use of insecticides for malaria control has led to an initially sharp decrease and recently rebound of Anopheles miminus, the key malaria vector in China and Southeast Asia. Not only has the insecticide-driven vector population succession restructured the vector community, but also the resurged mosquito population displayed altered biting preference. Based on these observations, we hypothesize that recent intensive malaria vector control measures and agricultural pest control measures have caused a significant ecological species succession and population genetic bottleneck of malaria vectors in Hainan Island, China. Therefore, this FIRCA proposal aims to take the advantage of geographical isolation of Hainan Island to elucidate the evolution of a major malaria vector in response to insecticide control. We will determine whether the different ecotypes of An. minimus from hilly and plain areas have different vectorial competence to Plasmodium falciparum infections. This study will provide invaluable information for the prediction of mosquito evolution in response to insecticides-based mosquito control measures in other malaria-endemic regions of Southeast Asia. The proposed research will contribute to building research capacity by training one Ph.D. student and one postdoc fellow from the endemic country. This project will be carried out primarily in China at Chongqing Normal University in collaboration with Dr. Bin Chen, as an extension of NIH grant U19 AI089672. PUBLIC HEALTH RELEVANCE: This application focuses on the mechanism of evolution of a major malaria vector species as a result of intensive insecticides-based malaria control measures in Hainan Island, southern China. Knowledge obtained from this study will help predict evolution of vector population in areas with extensive insecticide use, and help improve the effectiveness of vector control programs. Further, this research will contribute to strengthening international collaborations and building research capacity in malaria research in Chongqing Normal University.