Summer Internship Opportunity in Infectious Disease Ecology and Epidemiology
Lyme disease and anaplasmosis are zoonotic infections transmitted to humans by the
blacklegged tick, Ixodes scapularis. In recent years, I. scapularis has rapidly spread from the
northwestern region of Wisconsin, eastward into the north-central and southeastern parts of the
state. Coinciding with the spread of the tick is an increasing incidence of human infections.
Although a warming climate may be partially to blame, forest modification by deer, a keystone
species, may also be playing a role in these trends.
Deer are important blood meal hosts of the adult stages of the tick and in dispersal of the tick;
however, small rodents and birds are the preferred blood meal hosts of the larval and nymphal
tick stages and are essential hosts for maintenance of the pathogen life cycles. The effects of
deer browsing on forest vegetation have been intensively studied by Dr. Don Waller and his
students in the Department of Botany at UW-Madison. Results indicate that heavy deer
browsing suppresses tree seedling regeneration and converts the forest understory from that
dominated by herb and shrub species to that composed largely of grass and sedge species. In
addition, there is evidence to suggest that invasive plant species may have an advantage in
heavily deer browsed forests. All of these changes in understory vegetation have the potential to
influence the transmission dynamics of tick-borne pathogens by influencing the survival of ticks
in the environment, as well as the densities of rodent and bird populations. Thus, the overall
research questions relate to understanding how the effects of deer browsing influence disease
processes within ecological communities. By identifying specific relationships between deer,
forest vegetation and tick abundances, we may be able to provide new insight into the
complexities of the emergence of tick-borne diseases in Wisconsin and be better able to predict
where risks for humans are greatest. In addition, this research may have long-term implications
for deer and land management practices as they relate to public health and conservation.
The goals of the summer research position will be to begin exploring the relationships between
deer browsing activity, understory vegetation, and tick abundances. This exploration will
involve collaboration with members of the Waller laboratory, travelling to and conducting tick
sampling at forest sites across Wisconsin, and experimenting with different tick collection
methods. There will also be opportunities to assist with tick identifications, optimization of a
multiplex PCR assay to screen ticks for pathogens, and analysis of human epidemiologic data.
Interested individuals should contact:
Dr. Anna Schotthoefer
Marshfield Clinic Research Foundation
715-389-3520
Schotthoefer.Anna@mcrf.mfldclin.edu
And plan to apply to the Marshfield Clinic Research Foundation Summer Internship Program by
January 15, 2011:
http://www.marshfieldclinic.org/merc/pages/default.aspx?page=merc_edu_opp_program_details