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

University Of Pennsylvania, Philadelphia PA

Investigators

Abstract

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.