The Effects of a Complex Trophic Structure of Mammalian Host Species on the Ecology of Emerging Infectious Diseases

Abstract

Wildlife-parasite interactions among both ectoparasites and haemoparasites and their hosts are not well known among North American mammals, particularly in the case of relatively intact and complex communities of mammals that include top-level predators, large herbivores and a wide variety of rodent species. Understanding the distribution of haemoparasites among potential mammalian hosts can indicate links between hosts, biological vectors, disease agents, and human disease risk. This study examines the role and effects of a complex community of mammalian host species in maintaining the overall health of the ecosystem. Thereby, it explores the indirect and direct effects of wildlife in preventing the emergence of human infectious diseases depending upon land-use change/vegetation cover and host species richness. Rodents were captured and screened for blood parasites and ectoparasites in spring and summer 2011 within Grand Teton National Park (Figure 1). Sites were chosen by land-use /vegetation cover. Small blood samples from trapped individuals were collected and kept in lysis buffer/FTA cards. All the animals were released unharmed after blood sampling and ectoparasite collection. Collaborative efforts lead to collection of blood/tick samples from large predators, mesocarnivores and ungulates. Parasite DNA isolated from mammalian blood samples is being analyzed using the polymerase chain reaction and reverse line blot. DNA sequencing will be carried out to identify Plasmodium, Rickettsia Babesia, Borrelia, Ehrlichia, Hepatozoon, Anaplasma, and Theileria haemoparasites in the blood and in tick/flea samples.