Assessing risks of toxoplasmosis in wildlife in the Canadian North

人们对野生动物疾病（如禽流感）的出现所带来的风险的认识达到了前所未有的高度，但往往缺乏评估这些风险的科学基础。因此，我的研究计划的目标是为评估和减轻新出现的野生动物疾病所带来的风险建立一个强有力的科学基础，比如弓形虫病，这种疾病很可能是由迁徙的野生动物引入并维持在北极陆地上的。弓形虫病在加拿大北部尤为重要，因纽特人接触弓形虫病的比率是北美的三倍。此外，加拿大北部和土著居民的免疫系统疾病发病率普遍上升，这可能导致临床和先天性弓形虫病发病率上升。弓形虫病还可能导致北部野生动物的死亡和繁殖成功率下降，这些野生动物对土著和加拿大北部的收获、社会经济和文化原因很重要。因此，我的计划将解决：1)迁徙野生动物作为疾病引入和传播的机制有多重要？使用多种免疫学和分子技术，我将确定北方迁徙和居住野生动物弓形虫病的多样性和传播动态，并将其与其他地方的野生动物，家畜和人进行比较。2)寄生虫的哪些生活史策略使其能够在恶劣环境中成功生存？通过生存和传染性实验，我将确定北方野生动物弓形虫菌株是否具有独特的生物学特性（如耐寒性）。3)野生动物疾病在个体和种群层面上如何影响野生动物本身？圈养野生动物弓形虫病的控制实验感染和标记再捕获研究将确定感染状态、行为、身体状况、生存和繁殖成功之间的关系。我的研究项目将更好地了解一种重要疾病的生物学，开发一种新的方法来检测、评估和传达野生动物疾病出现带来的风险，并将使野生动物管理者、公共卫生人员以及北部和土著社区受益。

Awareness of the risks posed by the emergence of wildlife diseases (such as avian influenza) is at an all time high, but the scientific basis for assessing these risks is often lacking. Therefore, the objective of my research program is to develop a strong scientific foundation for assessing and mitigating the risks posed by emerging wildlife diseases, such as toxoplasmosis, which is likely introduced and maintained in the terrestrial Arctic by migratory wildlife. Toxoplasmosis is particularly important in the Canadian North, where Inuit have triple the North American rate of exposure to toxoplasmosis. As well, northern and indigenous Canadians in general have rising rates of immunocompromising diseases that may lead to higher rates of clinical and congenital toxoplasmosis. Toxoplasmosis may also cause mortality and decreased reproductive success in northern wildlife important to indigenous and northern Canadians for harvest, socioeconomic, and cultural reasons. Therefore, my program will address: 1) How important are migratory wildlife as a mechanism for disease introduction and transmission? Using multiple immunological and molecular techniques, I will determine diversity and transmission dynamics of toxoplasmosis in migratory and resident wildlife in the North, and compare this with wildlife, domestic animals, and people elsewhere. 2) What life history strategies of parasites enable successful establishment in harsh environments? Through survival and infectivity experiments, I will determine if strains of toxoplasmosis in northern wildlife possess unique biological characteristics (such as cold tolerance). 3) How do wildlife diseases affect wildlife themselves, at the individual and population levels? Controlled experimental infection of captive wildlife with toxoplasmosis and mark-recapture studies in the field will determine associations among infection status, behavior, body condition, survival, and reproductive success. My research program will provide better understanding of the biology of an important disease, develop a novel approach to detecting, assessing, and communicating risks posed by the emergence of wildlife diseases, and will benefit wildlife managers, public health personnel, and northern and indigenous communities.