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Colorado tick fever
Mountain tick fever; Mountain fever; American mountain fever
Colorado tick fever is a viral infection. It is spread by the bite of the Rocky Mountain wood tick ( Dermacentor andersoni ).
Causes
This disease is usually seen between March and September. Most cases occur in April, May, and June.
Colorado tick fever is seen most often in the western United States and Canada at elevations higher than 4,000 feet (1,219 meters). It is transmitted by a tick bite or, in very rare cases, by a blood transfusion.
Tick bite
Ticks are bugs that can attach to you as you brush past bushes, plants, and grass. Once on you, ticks often move to a warm, moist place on your body...
Symptoms
Symptoms of Colorado tick fever most often start 3 to 6 days after the tick bite. A sudden fever continues for 3 days, goes away, then comes back 1 to 3 days later for another few days. Other symptoms include:
- Feeling weak all over and muscle aches
- Headache behind the eyes
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Lethargy (sleepiness) or confusion
- Nausea and vomiting
- Rash (may be light-colored)
- Sensitivity to light ( photophobia )
- Skin pain
- Sweating
Exams and Tests
The health care provider will examine you and ask about your signs and symptoms. If the provider suspects you have the disease, you will also be asked about your outdoor activity.
Blood tests will usually be ordered. Antibody tests can be done to confirm the infection. Other blood tests may include:
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Complete blood count (
CBC
)
CBC
A complete blood count (CBC) test measures the following:The number of red blood cells (RBC count)The number of white blood cells (WBC count)The tota...
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Liver function tests
Liver function tests
Liver function tests are common tests that are used to see how well the liver is working. Tests include:AlbuminAlpha-1 antitrypsin Alkaline phosph...
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Treatment
There are no specific treatments for this viral infection.
The provider will make sure the tick is fully removed from the skin.
You may be told to take a pain reliever if you need it. DO NOT give aspirin to a child who has the disease. Aspirin has been linked with Reye syndrome in children. It may also cause other problems in Colorado tick fever.
Pain reliever
Over-the-counter (OTC) pain relievers can help relieve pain or lower a fever. Over-the-counter means you can buy these medicines without a prescript...
Reye syndrome
Reye syndrome is sudden (acute) brain damage and liver function problems. This condition does not have a known cause. This syndrome has occurred in ...
If complications develop, treatment will be aimed at controlling the symptoms.
Outlook (Prognosis)
Colorado tick fever usually goes away by itself and is not dangerous.
Possible Complications
Complications may include:
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Infection of the membranes covering the brain and spinal cord (
meningitis
)
Meningitis
Meningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges.
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Irritation and swelling of the brain (
encephalitis
)
Encephalitis
Encephalitis is irritation and swelling (inflammation) of the brain, most often due to infections.
Read Article Now Book Mark Article - Repeated bleeding episodes for no apparent cause
Call your provider if you or your child develops symptoms of this disease, if symptoms worsen or do not improve with treatment, or if new symptoms develop.
Prevention
When walking or hiking in tick-infested areas:
- Wear closed shoes
- Wear long sleeves
- Tuck long pants into socks to protect the legs
Wear light-colored clothing, which shows ticks more easily than darker colors. This makes them easier to remove .
Easier to remove
Ticks are small, insect-like creatures that live in woods and fields. They attach to you as you brush past bushes, plants, and grass. Once on you, ...
Check yourself and your pets frequently. If you find ticks, remove them right away by using tweezers, pulling carefully and steadily. Insect repellent may be helpful.
References
Beckham JD, Tyler KL. Encephalitis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Disease, Updated Edition . 8th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 91.
Bolgiano EB, Sexton J. Tick-borne illnesses. In: Marx JA, Hockberger RS, Walls RM, et al, eds. Rosen's Emergency Medicine . 8th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 134.
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Ticks - illustration
There are many species of ticks. Of these, a large proportion are capable of carrying disease. Diseases carried by ticks include Lyme disease, Erlichiosis, Rocky Mountain Spotted Fever, Colorado Tick Fever, tularemia, typhus, hemorrhagic fever, and viral encephalitis. (Image courtesy of the Centers for Disease Control and Prevention.)
Ticks
illustration
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Tick imbedded in the skin - illustration
This is a close-up photograph of a tick embedded in the skin. Ticks are important because they can carry diseases such as Rocky Mountain spotted fever, tularemia, Colorado tick fever, Lyme disease, and others.
Tick imbedded in the skin
illustration
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Antibodies - illustration
Antigens are large molecules (usually proteins) on the surface of cells, viruses, fungi, bacteria, and some non-living substances such as toxins, chemicals, drugs, and foreign particles. The immune system recognizes antigens and produces antibodies that destroy substances containing antigens.
Antibodies
illustration
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Deer ticks - illustration
Diseases are often carried by ticks, including Rocky Mountain Spotted Fever, Colorado Tick Fever, Lyme disease, and tularemia. Less common or less frequent diseases include typhus, Q-fever, relapsing fever, viral encephalitis, hemorrhagic fever, and babesiosis.
Deer ticks
illustration
-
Ticks - illustration
There are many species of ticks. Of these, a large proportion are capable of carrying disease. Diseases carried by ticks include Lyme disease, Erlichiosis, Rocky Mountain Spotted Fever, Colorado Tick Fever, tularemia, typhus, hemorrhagic fever, and viral encephalitis. (Image courtesy of the Centers for Disease Control and Prevention.)
Ticks
illustration
-
Tick imbedded in the skin - illustration
This is a close-up photograph of a tick embedded in the skin. Ticks are important because they can carry diseases such as Rocky Mountain spotted fever, tularemia, Colorado tick fever, Lyme disease, and others.
Tick imbedded in the skin
illustration
-
Antibodies - illustration
Antigens are large molecules (usually proteins) on the surface of cells, viruses, fungi, bacteria, and some non-living substances such as toxins, chemicals, drugs, and foreign particles. The immune system recognizes antigens and produces antibodies that destroy substances containing antigens.
Antibodies
illustration
-
Deer ticks - illustration
Diseases are often carried by ticks, including Rocky Mountain Spotted Fever, Colorado Tick Fever, Lyme disease, and tularemia. Less common or less frequent diseases include typhus, Q-fever, relapsing fever, viral encephalitis, hemorrhagic fever, and babesiosis.
Deer ticks
illustration
Review Date: 11/27/2016
Reviewed By: Arnold Lentnek, MD, Infectious Diseases Medical Practice of NY and Clinical Research Centers of CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
