|Normal range in red; other reports in blue|
Dermacentor variabilis, also known as the American dog tick or Wood tick, is a species of tick that is known to carry bacteria responsible for several diseases in humans, including Rocky Mountain spotted fever and tularemia (Francisella tularensis). It is one of the most well-known hard ticks. Diseases are spread when it sucks blood from the host, which could take several days for the host to experience some symptoms.
Though D. variabilis may be exposed to Borrelia burgdorferi, the causative agent of Lyme disease, these ticks are not competent vectors for the transmission of this disease. The primary vector for Borrelia burgdorferi is the deer tick Ixodes scapularis in Eastern parts of the United States, and Ixodes pacificus in California and Oregon. Dermacentor variabilis may also carry Anaplasma phagocytophilum, the causative agent of HGE (human granulocytic ehrlichiosis), and Ehrlichia chaffeensis, the causative agent of HME (human monocytic ehrlichiosis).
Dermacentor ticks may also induce tick paralysis by elaboration of a neurotoxin that induces rapidly progressive flaccid quadriparesis similar to Guillain-Barré syndrome. The neurotoxin prevents presynaptic release of acetylcholine from neuromuscular junctions.
- Piesman J, Sinsky RJ (September 1988). "Ability to Ixodes scapularis, Dermacentor variabilis, and Amblyomma americanum (Acari: Ixodidae) to acquire, maintain, and transmit Lyme disease spirochetes (Borrelia burgdorferi)". J. Med. Entomol. 25 (5): 336–9. PMID 3193425.
- Kevin Holden, John T. Boothby, Sulekha Anand & Robert F. Massung (2003). "Detection of Borrelia burgdorferi, Ehrlichia chaffeensis, and Anaplasma phagocytophilum in Ticks (Acari: Ixodidae) from a Coastal Region of California". J. Med. Entomol. 40 (4): 534–9. doi:10.1603/0022-2585-40.4.534. PMID 14680123.
- Joseph Piesman & Christine M. Happ (1997). "Ability of the Lyme disease spirochete Borrelia burgdorferi to infect rodents and three species of human-biting ticks (blacklegged tick, American dog tick, lone star tick) (Acari:Ixodidae)". J. Med. Entomol. 34 (4): 451–6. PMID 9220680.
- F. H. Sanders & J. H. Oliver (1995). "Evaluation of Ixodes scapularis, Amblyomma americanum, and Dermacentor variabilis (Acari: Ixodidae) from Georgia as vectors of a Florida strain of the Lyme disease spirochete, Borrelia burgdorferi". J. Med. Entomol. 32 (4): 402–426. PMID 7650697.
- Stanley W. Mukolwe, A. Alan Kocan, Robert W. Barker, Katherine M. Kocan & George L. Murphy (1992). "Attempted transmission of Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) (JDI strain) by Ixodes scapularis (Acari: Ixodidae), Dermacentor variabilis, and Amblyomma americanum". J. Med. Entomol. 29 (4): 673–7. PMID 1495078.
- Ohio State University Extension Fact Sheet
- Illinois photographs
- Iowa tick images
- Dealing with dog ticks
- American dog tick on the University of Florida / Institute of Food and Agricultural Sciences Featured Creatures website