Ecology of Powassan/Deer tick virus in eastern New York State

纽约州东部 Powassan/鹿蜱病毒的生态学

基本信息

批准号：
8005403
负责人：
Laura D Kramer
金额：
$ 22.59万
依托单位：
WADSWORTH CENTER
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-05-01 至 2012-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8005403
关键词：
American Anaplasma phagocytophilum Arboviruses Asia Awareness Biological Assay Biology Birds Black-legged Tick Borrelia burgdorferi Case Fatality Rates Cell Culture Techniques Characteristics Competence Complex Culicidae Deer Tick Diagnosis Diagnostic Reagent Disease model Ecology Ecosystem Encephalitis Europe European Tick-Borne Encephalitis Flavivirus Foundations Frequencies Future Genetic Goals Gray unit of radiation dose Growth Health Human In Vitro Infection Institutes Ixodes Laboratories Location Lyme Disease Mammals Modeling Morbidity - disease rate Nature Neurologic Neutralization Tests New York North America Oral candidiasis Patients Phylogenetic Analysis Pilot Projects Population Population Density Powassan Encephalitides Powassan virus Prevalence Property Public Health Research Research Personnel Risk Rivers Robin bird Role Series Seroprevalences Site Source St. Louis Encephalitis Virus Testing Tick-Borne Diseases Tick-Borne Encephalitis Tick-Borne Encephalitis Virus Tick-Borne Encephalitis Viruses Ticks Time Vaccines Variant Vertebrate Viruses Viral Viremia Virus West Nile virus Wood material Woodchuck base enzootic expectation feeding field study improved in vivo mortality pathogen prototype public health relevance research study surveillance study transmission process vector

项目摘要

DESCRIPTION (provided by applicant): Powassan virus (POWV), a North American tick-borne flavivirus (Flaviridae; flavivirus), is related to Old World tick-borne encephalitis (TBE) viruses found in Asia and Europe. Phylogenetic analyses of isolates indicated two lineages of POWV, prototype POWV transmitted predominantly by Ixodes cookei, and an antigenic variant, deer tick virus (DTV), transmitted by Ixodes scapularis. Although infections with POWV and DTV have been detected in various mammals, which of these species act as important reservoirs is unknown. Increased human surveillance following the introduction of West Nile virus into North America, and improved diagnostic reagents have demonstrated increased prevalence in North America of serious infection with POWV/DTV in humans. The overall goals of this study are to elucidate the dynamics of transmission of this emerging flavivirus and to provide the foundation for understanding risk. Our hypothesis is that POWV, and especially its antigenic variant, DTV, represent an emerging tick-borne pathogen that presents an increasing risk to humans as a consequence of burgeoning tick populations in the northeastern US. Integrated field and lab studies will (1) determine the environmental burden of POWV in ticks and their vertebrate hosts at enzootic foci; (2) determine which host(s) is responsible for infecting tick vectors; (3) further characterize the biology and ecology of POWV (and DTV); and (4) assess the role of birds as potential sources of virus for questing ticks. This pilot study will provide the foundation and guidance for future exhaustive efforts to understand spatial/temporal genetic differences between Lineage 1 (prototype POWV) and Lineage 2 (DTV) Powassan virus, geographic scope of transmission activity, role of co-feeding, and robust vector and host competence experiments. PUBLIC HEALTH RELEVANCE: Powassan encephalitis, caused by Powassan virus and its antigenic variant, deer tick virus, is of significant public health importance because of its serious nature in spite of its rarity. It is associated with significant long- term morbidity including severe neurologic sequelae with a case-fatality rate of 10%-15%. Because there is no vaccine or specific therapy for Powassan encephalitis, it is important to understand the ecology of the causative agent and how this virus interacts with its tick vectors and vertebrate hosts.

描述（由申请人提供）：Powassan病毒（POWV）是一种北美tick虫的黄病毒（Flaviridae; Flavivivirus），与在亚洲和欧洲发现的旧世界tick传播脑炎（TBE）病毒有关。分离株的系统发育分析表明POWV的两个谱系，原型POWV主要由ixodes cookei传播，以及由ixodes scapularis传播的抗原变体鹿tick病毒（DTV）。尽管已经在各种哺乳动物中检测到了POWV和DTV的感染，但这些物种中的哪种是重要的储层。将西尼罗河病毒引入北美后，人类的监测增加，改善的诊断试剂表明，北美的患病率增加了人类严重感染的POWV/DTV。这项研究的总体目标是阐明这种新兴的黄病毒的传播动态，并为理解风险提供基础。我们的假设是，POWV，尤其是其抗原变体DTV代表了一种新兴的tick传播病原体，由于美国东北部迅速迅速的tick虫种群，对人类的风险增加了。（1）综合领域和实验室研究将确定tick中POWV及其脊椎动物宿主在Enzootic Foci中的环境负担；（2）确定哪个主机负责感染壁虱向量；（3）进一步描述了POWV（和DTV）的生物学和生态学；（4）评估鸟类作为Quest tick病毒的潜在来源的作用。这项试点研究将为未来的详尽努力提供基础和指导，以了解谱系1（Prototype powv）和谱系2（DTV）Powassan病毒之间的空间/时间遗传差异，传播活动的地理范围，共同进食的作用，以及鲁棒矢量和宿主和宿主的能力实验。公共卫生相关性：Powassan脑炎，由Powassan病毒及其抗原变体鹿tick病毒引起，尽管其稀有性，但由于其严重的性质，公共健康的重要性非常重要。它与显着的长期发病率有关，包括严重的神经系统后遗症，病例式率为10％-15％。由于没有针对Powassan脑炎的疫苗或特定疗法，因此重要的是要了解病因的生态学以及该病毒如何与其tick矢量和脊椎动物宿主相互作用。