Tick-borne Disease Risk along the Appalachian Trail

Each year, 2-3 million visitors walk a portion of the Appalachian Trail, engaged in outdoor activities where exposure to ticks is likely. While the trail passes through the states with the greatest number of cases of Lyme disease and Rocky Mountain Spotted Fever, it is unknown how many people become sick after visiting the trail. This paper assesses tick-borne disease risk in the National Park Service (NPS) units located along the Appalachian Trail, and finds that the disease risk is unknown, and likely under recognized. It is recommended that tick sampling as part of a larger tick-borne disease surveillance program be implemented in the national parks. As a starting point to further study, general tick habitat suitability was modeled for the NPS units along the Appalachian Trail based on land cover, elevation and moisture. Potential tick sampling sites were selected based on areas of high tick habitat suitability and high visitor use.