Jenny
Guha
Jim
Sara
Tim S.
Zach
Tim E.
Cecilia
Jessie
BillDisease Ecology
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Ongoing Projects Parasite Genetics Raccoon Disease Ecology Raccoon Roundworm |
Two of the most important areas of current research in disease ecology are emerging infectious diseases (EIDs) and spreading resistance genes (SRGs). Although they seem disparate, both these fields of research are concerned with the ability of parasites to adapt to novel host defense mechanisms, whether pharmaceutical or immunological. Thus, it is clear that in order to obtain a better understanding of EIDs and SRGs, we need a greater understanding of gene dynamics in parasite populations. Unfortunately, our comprehension of the factors influencing gene dynamics in parasite populations is still based, to a large degree, on theoretical research and what is now urgently required is more empirical data. Our research focuses on improving our empirical understanding of factors influencing the gene dynamics at two fundamental scales of the parasite population: the infrapopulation (all parasites of a particular species in an individual host at a particular time) and the component population (all individuals of a specified life history phase at a particular place and time). The biological system that our research centers upon is that of a host and two of its parasites, with each parasite having different life history characteristics. The parasites are two species of ticks, the American dog tick (Dermacentor variabilis) and the raccoon tick (Ixodes texanus), that parasitize the raccoon (Procyon lotor). The first major focus area of this research is in trying to understand the transmission dynamics of the two species of ticks at the scale of the individual host. Secondly, we want to increase our understanding of factors that help in the shaping the genetic structuring of the two species of ticks that each have vastly different life history charecteristics. Thirdly, we plan on comparing the genetic co-structuring of the two tick species with that of their host, the raccoon. Lastly, we hope to evaluate if popualtion genetic structure of parasite populations is stable at micro-temporal scales, in order to assesss if molecular markers can be used to evaluate parasite effective population sizes.
Funding Source: Purdue Center for the Environment
Personnel: Guha Dharmarajan, Jim Beasley, Jenny Fike
Publications:
Dharmarajan, G., J.A. Fike, J.C. Beasley, and O.E. Rhodes, Jr. 2008. Development and characterization of 12 polymorphic microsatellite loci in American dog tick (Dermacentor variablis). Molecular Ecology Resources. (In Press)
Collaborators: Kevin Kazacos, Kristen Page
Raccoon photo: Jim Beasley
The adaptability of raccoons to human inhabited areas presents opportunities for exposure of humans and domestic animals to diseases carried by raccoons, with resultant illness, decreased productivity and monetary loss from infectious diseases. In spite of the potential risk posed by raccoons to human and livestock health our understanding of disease dynamics or efficacy of potential control strategies in this species is limited, with the possible exception of raccoon rabies.The dynamics of disease in wild animals is usually complex, being affected by a horde of host and landscape features and thus requires a multi-disciplinary approach. To this end we have brought together a team of experts from the disciplines of ecology, epidemiology, microbiology and virology. The first goal of this project is to identify of diseases that may be transmitted to livestock at the livestock-raccoon interface, including Bovine Viral Diarrhea and Porcine reproductive and respiratory syndrome. And secondly, by integrating epidemiological data and GIS data with the large body ecological data collected from raccoons in our study area, we hope to increase our understanding of the ecological, epidemiological and landscape related risk factors that may be associated with prevalence of specific livestock diseases in raccoon populations.
Funding Source: Purdue Center for the Environment
Personnel: Guha Dharmarajan, Jim Beasley
Publications:
In Progress
Collaborators: Ching Ching Wu, Eran Raizeman, Roman Pogranichniy
Researchers from the departments of Forestry and Natural Resources and Veterinary Pathobiology at Purdue as well as from Ohio State University and Wheaton College are working together to develop a cost-effective treatment regime for controlling the prevalence of raccoon roundworm in rural and urban environments, thereby improving quality of life for the general populace by decreasing human health risks associated with exposure to this parasite. The ultimate goal of the project, led by Gene Rhodes in Forestry and Natural Resources, is to establish a strategy for the distribution of medicated baits that when eaten, will deworm wild raccoons and minimize the probability of human infection by this potentially lethal parasite. Alarmingly high numbers of raccoons in rural agricultural landscapes and suburban neighborhoods have raised public concerns about the potential exposure of children to raccoon roundworm, which is highly prevalent in raccoons throughout northern Indiana and much of the Midwest. This project is built upon a foundation of previous research by members of the research team that has revealed a wealth of critical information about the ecology of both the parasite and its raccoon host in the agricultural landscapes of northern Indiana. The successful development of treatment strategies for raccoon roundworm will lead to improved quality of life for individuals living in areas where raccoon roundworm exposure is a threat as well as to opportunities for economic development as a service industry for delivering parasite treatments in both rural and urban environments emerges.
Funding Source: Purdue Center for the Environment
Personnel: Tim Eagan, Tim Smyser, Jim Beasley
Publications:
In Progress
Collaborators: Kristen Page, Stan Gehrt, Kevin Kazacos