What is Colorado tick fever?

Colorado tick fever is an illness caused by a virus carried by small mammals, such as ground squirrels, porcupines and chipmunks, and transmitted through the bite of a tick.

Who gets Colorado tick fever?

Anyone can get Colorado tick fever who lives or travels in areas of the western United States and Canada at elevations above 5,000 feet and who comes in contact with infected ticks, especially Dermacentor Anderson.

How is Colorado tick fever spread?

People get Colorado tick fever following a tick bite. There is no evidence of natural person-to-person transmission. However, rare cases of transmission from blood transfusions have been reported. The virus that causes Colorado tick fever may stay in the blood for as long as four months after onset of the illness.

What are the symptoms of Colorado tick fever?

The disease causes:

• High fever
• Chills
• Nausea
• Severe headache

These symptoms usually last a few days, go away, and then return for a few days. Occasionally a rash appears.

How soon do symptoms usually appear?

The symptoms generally begin four to five days after being bitten by an infective tick.

How should a tick be removed?

• Ticks should be removed promptly and carefully by using tweezers and applying gentle steady traction.
• Do not crush the tick’s body when removing it and apply the tweezers as close to the skin as possible to avoid leaving parts of the tick’s mouth in the skin.
• Do not remove ticks with your bare hands.
• Protect your hands with gloves, cloth or tissue and be sure to wash your hands after removing a tick.

How can Colorado tick fever be prevented?

• Avoid tick-infested areas, especially during the warmer months.
• Wear light-colored clothing so ticks can be easily seen. Wear a long-sleeved shirt, hat, long pants, and tuck your pant legs into your socks.
• Walk in the center of trails to avoid overhanging grass and brush.
• Check your body every few hours for ticks when you spend a lot of time outdoors in tick-infested areas. Ticks are most often found on the thigh, arms, underarms and legs. Ticks can be very small (no bigger than a pinhead). Look carefully for new “freckles.”
• Use insect repellents containing DEET on your skin (except the face) or permethrin on clothing. Be sure to follow the directions on the container and wash off repellents when going indoors.
• Remove attached ticks immediately.

Where can I get more information?

Contact your doctor or the Southern Nevada Health District, Office of Epidemiology at (702) 759-1300.