Indicators for elevated risk of human exposure to host-seeking adults of the Rocky Mountain wood tick (Dermacentor andersoni) in Colorado.

نویسندگان

  • Lars Eisen
  • Luis A Ibarra-Juarez
  • Rebecca J Eisen
  • Joseph Piesman
چکیده

The human-biting adult stage of the Rocky Mountain wood tick (Dermacentor andersoni) can cause tick paralysis in humans and domestic animals and is the primary tick vector in the intermountain west of the pathogens causing Colorado tick fever, Rocky Mountain spotted fever, and tularemia. We conducted drag sampling studies in Poudre Canyon and Rocky Mountain National Park of Larimer County, CO, to determine microhabitat use patterns by host-seeking D. andersoni adults and find environmental factors signaling elevated risk of tick exposure. Big sagebrush (Artemisia tridentata) was found to serve as a general indicator of areas with elevated risk of exposure to host-seeking D. andersoni adults; this likely results from a shared climate tolerance of big sagebrush and D. andersoni. Grass was the favored substrate for host-seeking ticks. Drag sampling of open grass or grass bordering rock or shrub produced abundances of D. andersoni adults significantly higher than sampling of brush. Sampling sites in Rocky Mountain National Park, relative to Poudre Canyon, were characterized by more intense usage by elk (Cervus elaphus) but decreased brush coverage, smaller brush size, and lower abundances of host-seeking D. andersoni adults. There has been a tremendous increase in the population of elk in Rocky Mountain National Park over the last decades and we speculate that this has resulted in an ecological cascade where overgrazing of vegetation by elk is followed by suppression of rodent populations, decreased tick abundance, and, ultimately, reduced risk of human exposure to D. andersoni and its associated pathogens.

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منابع مشابه

MODELING/GIS, RISK ASSESSMENT, ECONOMIC IMPACT Climate-Based Model Predicting Acarological Risk of Encountering the Human-Biting Adult Life Stage of Dermacentor andersoni (Acari: Ixodidae) in a Key Habitat Type in Colorado

We exploited an elevation (climate) gradient ranging from 1,700 to 2,500 m in Poudre Canyon of LarimerCounty, CO, to determine climatic correlates of abundance per 15-s drag sampling time unit (hereafter referred to as abundance) of the human-biting adult life stage of the Rocky Mountain wood tick, Dermacentor andersoni Stiles (Acari: Ixodidae), in a key risk habitat for tick exposure: south/we...

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SAMPLING, DISTRIBUTION, DISPERSAL Distribution, Seasonality, and Hosts of the Rocky Mountain Wood Tick in the United States

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عنوان ژورنال:
  • Journal of vector ecology : journal of the Society for Vector Ecology

دوره 33 1  شماره 

صفحات  -

تاریخ انتشار 2008