Colorado Tick Fever
Condition
(CTF)
Definition
Colorado tick fever is a rare viral infection from a tick bite. For most, the infection is mild. Rarely, it can affect the nervous system.
Causes
Colorado tick fever is caused by the Colorado tick fever virus. People can get the virus from the bite of an infected tick.
The virus is not passed from person to person. Rarely, it has been passed from a transfusion of infected blood.
Colorado tick fever is transmitted through the bite of an infected tick.
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Risk Factors
Colorado tick fever is found in the Rocky Mountains of North America. It is also found in the western United States and parts of Canada. The risk of getting the virus is highest for those who live in or travel to these regions, especially:
- In mountain forest areas with heights of 4,000 to 10,000 feet
- Between April and July
Symptoms
Symptoms usually appear 3 to 5 days after a tick bite. They may last for 3 weeks.
Symptoms of Colorado tick fever may be:
- High fever and chills
- Severe headache
- Eye redness, sensitivity to light, or pain behind the eyes
- Muscle pain
- Feeling tired or weak
- Nausea and vomiting
- Diarrhea
- Rash
Diagnosis
The doctor will ask about symptoms and past health. You may be asked about exposure to places where ticks are present. A physical exam will be done. Blood tests may be done to look for signs of the virus.
Treatment
There is no specific treatment for Colorado tick fever. Most people recover in about a week. The goal is to ease symptoms. This can be done with pain relievers and by drinking plenty of fluids.
Prevention
Avoid tick-infested areas when possible. To lower the risk of Colorado tick fever:
- Wear light-colored clothing. Tuck pants into socks. Put clothes in the dryer for 20 minutes after wearing to kill any ticks.
- Use tick repellents.
- Check for ticks often. Properly remove any ticks. Take a bath or shower after.
- Wash tick bites with soap and water after removing a tick.
Centers for Disease Control and Prevention
National Institute of Allergy and Infectious Diseases
Centers for Disease Control and Prevention
National Institute of Allergy and Infectious Diseases
References
- Colorado tick fever. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/colorado-tick-fever.
- Eickhoff C, Blaylock J. Tickborne diseases other than Lyme in the United States. Cleve Clin J Med. 2017;84(7):555-567.
- Tick avoidance and removal. EBSCO DynaMed website. Available at: https://www.dynamed.com/prevention/tick-avoidance-and-removal-14.
Contributors
- David L. Horn, MD, FACP
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