RAPID: Do extreme climatic events and predator diversity interact to shape the biogeography of disease?

这项研究将提供关于Sin Nombre病毒（SNV）的关键信息，有助于提高每年数十万国家公园游客的安全，并涉及两名研究生和一名博士后科学家。许多影响人类的疾病（如莱姆病、汉坦病毒、西尼罗河病、狂犬病、弓形虫病）都是人畜共患疾病，即以动物为主要宿主的疾病。因此，了解控制动物疾病流行的生态力量对于了解人类疾病风险非常重要。然而，预测疾病流行可能很困难，因为动物种群的大小可能受到捕食者和资源可用性（例如动物可获得的食物量）的影响。由于气候（如年降水量）往往决定资源的可得性，了解捕食者和资源可得性如何相互作用影响宿主种群可能会因极端气候事件而变得更加复杂。极端气候事件在未来气候情景下可能会变得更加常见。此外，人类活动正在改变全球顶级捕食者的分布，可能会影响捕食者对动物种群的影响。尽管了解捕食者和气候如何塑造疾病很重要，但这类研究具有挑战性，因为捕食者很少被确定，而且极端气候事件可能发生得如此之快，以至于很难对它们进行研究。该研究项目将利用已知捕食者多样性的多个岛屿生态系统，提供一个前所未有的机会，了解极端气候事件和捕食者多样性如何影响Sin Nombre病毒（SNV）的流行，SNV导致汉坦病毒肺综合征，这是一种严重的人类疾病。具体来说，这项研究需要测量加州海峡群岛鹿鼠中SNV的流行情况，在干旱期间和之后，这是过去500年来最严重的干旱。这些数据，特别是与现有的干旱前数据相结合，提供了一个难得的机会来了解极端气候事件与捕食者之间在影响疾病大规模流行方面的相互作用，也提供了一个机会来评估捕食者多样性降低动物种群中疾病流行反弹速度的新假设。

This research will provide critical information on the Sin Nombre Virus (SNV) that can help improve the safety of hundreds of thousands of National Park visitors each year, as well as involve two graduate students and a postdoctoral scientist. Many diseases that affect humans (e.g. Lyme disease, hantaviruses, West Nile disease, rabies, toxoplasmosis) are zoonotic diseases, i.e. diseases where an animal is the primary host for the disease. As a result, understanding the ecological forces that govern the prevalence of disease in animals is very important for understanding human disease risk. However, predicting disease prevalence can be difficult because the size of animal populations is likely affected by both predators and by resource availability (e.g. the amount of food available for animals). Understanding how predators and resource availability interact to affect host populations may be further complicated by extreme climatic events that may become more common under future climate scenarios, since climate (e.g. the amount of annual precipitation) often determines resource availability. In addition, human activities are changing the worldwide distribution of top predators, likely affecting the nature of predator effects on animal populations. Despite the importance of understanding how predators and climate shape disease, such research is challenging because predators are rarely known with certainty, and because extreme climatic events may occur so rapidly that it is difficult to study them. This research project will use multiple island ecosystems where predator diversity is known, providing an unprecedented opportunity to understand how extreme climatic events and predator diversity affect the prevalence of Sin Nombre Virus (SNV), which causes hantavirus pulmonary syndrome, a severe disease in humans. Specifically, this research entails measuring SNV prevalence in deer mice on the California Channel Islands during and after a drought more severe than any drought in the last 500 years. These data, especially when coupled with existing pre-drought data, provide a rare opportunity to understand the interplay between extreme climatic events and predators in affecting large-scale prevalence of disease, and also provides an opportunity to evaluate the novel hypothesis that predator diversity reduces the rate at which disease prevalence rebounds in animal populations.