Colorado tick fever is an infection that is transmitted to humans by the bite of an infected tick.
Colorado tick fever is caused by the Colorado tick fever virus. Humans can get the virus through the bite of an infected tick. The Rocky Mountain wood tick is the principal carrier of the Colorado tick virus in the US, and its geographic range is confined to the western US states and areas above 5,000 ft. in elevation.
The virus is also carried by other small mammals, including ground squirrels, porcupines, and chipmunks. There have been reports of rare cases of Colorado tick fever caused by exposure in a laboratory setting and a blood transfusion.
Living or traveling in mountain forest areas at altitudes above 5,000 feet in the Rocky Mountain region, especially between April and July, increases your chances of developing Colorado tick fever. If you have been in these areas, tell your doctor.
If you experience any of these symptoms do not assume it is caused by Colorado tick fever. These symptoms may be attributed to other, less serious health conditions. If you experience any one of them, see your physician. Symptoms usually appear 4-5 days after a tick bite occurs.
Your doctor will ask about your symptoms and medical history, and perform a physical exam.
Tests may include the following:
There is no specific treatment for Colorado tick fever. Complications are extremely rare and include aseptic meningitis, encephalitis, and hemorrhagic fever. The fever and pain may be treated with acetaminophen (eg, Tylenol) and other pain relief medications. Once a person gets Colorado tick fever, it is believed that he or she will have immunity against re-infection.
To help reduce your chances of getting Colorado tick fever, take the following steps to limit your exposure to ticks:
Centers for Disease Control and Prevention
National Institute of Allergy and Infectious Diseases
Canadian Cooperative Wildlife Health Centre
Public Health Agency of Canada
Colorado tick fever. Utah Department of Health website. Available at: http://health.utah.gov/els/epidemiology/epifacts/ctf.html . Accessed October 27, 2006.
Colorado tick fever fact sheet. Oregon.gov website. Available at: http://www.oregon.gov/DHS/ph/acd/diseases/ctf/facts.shtml . Accessed October 27, 2006.
Colorado tick fever. Medline Plus website. Available at : http://www.nlm.nih.gov/medlineplus/ency/article/000675.htm . Accessed February 12, 2008.
Last reviewed November 2008 by David L. Horn, MD, FACP
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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