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Colorado tick fever (CTF) virus is spread to people through bites of infected ticks. People who live in or visit areas in the western United States or western Canada that are 4,000‒10,000 feet above sea level may be at risk of becoming infected. Most cases of CTF occur during spring and summer months when ticks are most active. The most common symptoms of CTF are fever, chills, headache, body aches, and feeling tired. There are no medications to treat or vaccines to prevent CTF.

The best way to prevent CTF is to reduce your risk of tick bites.

  • Use insect repellent
  • Wear long sleeves and pants
  • Avoid wooded and bushy areas with high grass
  • Perform thorough tick checks after spending time outdoors

Talk to your health-care provider if you think you or a family member may have CTF.

  Image of a male and female rocky mountain wood tick