COLLABORATIVE RESEARCH: Ecological consequences of the effects of a zoonotic pathogen on its reservoir host

人类的许多传染病都是由野生动物传播的病原体引起的。一个重要的例子是莱姆病，这种疾病的细菌病原体生活在小型哺乳动物体内，如白足鼠，并通过蜱虫传播给人类，蜱虫首先叮咬受感染的老鼠，然后叮咬人。人类患莱姆病的风险随着白足鼠数量的增加而增加。研究人员最近收集的数据表明，感染莱姆病细菌的小鼠比未感染的小鼠平均寿命长17%。这是一个出乎意料的发现，因为这种细菌会导致人类和其他动物生病。这一点很重要，因为寿命延长可能导致受感染小鼠的数量增加。细菌是如何延长老鼠的寿命的？疾病传播给其他哺乳动物（包括人类）和森林生态系统的后果是什么？本研究将通过实验确定莱姆菌对：(1)小鼠存活和数量的影响；(2)小鼠觅食行为；(3)蜱虫叮咬老鼠的频率；(4)蜱虫的其他宿主（非老鼠）受感染的比率；(5)老鼠控制外来森林害虫舞毒蛾种群的能力。拟议的研究将为宾夕法尼亚大学的社区科学项目提供内容材料和研究经验。该项目旨在提高费城市中心高中教师对生物学的理解，并让高中生接触科学研究和科学事业。莱姆病是北美和其他地区人类常见和严重的问题。研究人员将开发并测试一种疫苗，以保护小鼠免受导致该疾病的病原体的侵害。如果这种疫苗像预期的那样起作用，它可能会减少病原体向人类的传播。通过对野生小鼠进行精心设计的实验，研究人员将能够评估野生动物疫苗接种的预期和潜在的意外后果。

Many infectious diseases of humans are caused by pathogens that are transmitted from wildlife. One important example is Lyme disease, in which the bacterial pathogen lives inside small mammals, such as the white-footed mouse, and is transmitted to people by ticks that first bite an infected mouse and then a person. Human risk of Lyme disease increases with the abundance of white-footed mice. Recent data collected by the investigators suggest that mice infected with the Lyme disease bacterium live, on average, 17% longer than do uninfected mice. This is an unexpected finding, given that the bacterium causes illness in people and other animals. It is important because longer life spans likely result in larger populations of infected mice. How might the bacterium increase life span in mice and what are the consequences for disease transmission to other mammals (including humans) and for the forest ecosystem?This research will experimentally determine the effects of the Lyme bacterium on: (1) mouse survival and abundance; (2) mouse foraging behavior; (3) how commonly mice are bitten by ticks; (4) the rate at which other (non-mouse) hosts for the tick become infected; and (5) the ability of mice to control populations of an exotic forest pest, the gypsy moth. The proposed research will provide both content material and research experiences for the Community Science program at the University of Pennsylvania. This program is designed to increase the understanding of biology by high school teachers in inner-city Philadelphia schools and to expose high school students to scientific research and careers in science. Lyme disease is a common and serious problem for humans in North America and elsewhere. The investigators will develop and test a vaccine to protect mice species from the pathogen that causes the disease. If this vaccine works as expected, it may reduce transmission of the pathogen to humans. Through a carefully designed experiment on wild mice, the investigators will be able to evaluate both the intended and potential unintended consequences of wildlife vaccination.