Emergence and adaption of West Nile virus in New York

描述：（由申请人提供）：西尼罗河病毒（WNV）已出现在 近年来，在欧洲、东欧、中东等温带地区， 在北美，它对人类、马和鸟类构成威胁， 健康该病毒于1999年首次在西半球被发现， 在纽约市附近的一个有限区域内， 发现感染。在2000年，西尼罗河病毒阳性的鸟类被确定从更广泛的 美国的地理区域，包括东北部的12个州， 从新罕布什尔州到北卡罗来纳州。虫媒病毒的出现和适应 疾病涉及内在（病毒、脊椎动物宿主）之间复杂的相互作用 和节肢动物媒介）和外在（环境条件，宿主种群 指数等）影响病毒传播周期的因素。引入 西尼罗河病毒进入天真的人口提供了一个独特的和历史性的机会， 前瞻性地研究西尼罗河病毒的出现和适应。拟议研究 将研究脊椎动物和无脊椎动物的相互关系 随着时间的推移，携带病毒的宿主会影响病毒和宿主种群。研究将 解决病毒传播周期的三个内在组成部分： 1.脊椎动物：研究将分析发病率、病毒血症、体液免疫 反应和遗传学的西尼罗河病毒感染的鸟类，并将检查这些变化 在五年的研究中。 2.矢量研究将在空间和时间上分析不同的人群 尖音库蚊的媒介能力、遗传标记和对病毒的影响 遗传多样性和适应性。 3.病毒：研究将分析病毒传播周期如何影响病毒 遗传和健身和病毒的能力，以适应温带 美国东北部的环境待评估的周期包括交替 鸟-蚊子通道，鸟之间的连续通道，连续通道 蚊虫之间的相互作用，以及宿主由鸟蚊向哺乳类蚊的转换 周期

DESCRIPTION: (provided by the applicant): West Nile virus (WNV) has emerged in recent years in temperate regions of Europe, Eastern Europe, the Middle East, and North America, where it presents a threat to human, equine and avian health. The virus was first identified in the Western Hemisphere in 1999 when humans, mosquitoes, birds and horses in a limited area near New York City were found infected. In year 2000, WNV positive birds were identified from a wider geographic area of the United States including 12 states in the northeast, from New Hampshire to North Carolina. The emergence and adaptation of arboviral diseases involve complex interactions between intrinsic (virus, vertebrate host and arthropod vector) and extrinsic (environmental conditions, host population indices, etc.) factors affecting the virus transmission cycle. The introduction of WNV into naive populations presents a unique and historic opportunity to prospectively study the emergence and adaptation of WNV. The proposed research will examine how the interrelationships of the vertebrate and invertebrate hosts with the virus affect virus and host populations over time. Research will address three intrinsic components of the virus transmission cycle: 1. Vertebrate: Studies will analyze the morbidity, viremia, humoral immune response, and genetics of WNV infected birds and will examine changes in these factors over the five-year study. 2. Vector Studies will analyze spatially and temporally, disparate populations of Culex pipiens for vector competence, genetic markers, and effects on viral genetic diversity and fitness. 3. Virus: Studies will analyze how the virus transmission cycle impacts viral genetics and fitness and the ability of the virus to adapt to the temperate environment of northeastern USA. The cycles to be evaluated include alternating bird-mosquito passages, sequential passages between birds, sequential passages between mosquitoes, and host switching from bird-mosquito to mammal-mosquito cycle.