BACK TOTOP Browse A-ZSearchBrowse A-ZABCDEFGHIJKLMNOPQRSTUVWXYZ0-9 E-mail FormEmail ResultsName:Email address:Recipients Name:Recipients address:Message: Print-FriendlyBookmarksbookmarks-menuColorado tick feverMountain tick fever; Mountain fever; American mountain feverColorado tick fever (CTF) 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.CTF is seen most often in the western United States and Canada at elevations higher than 4,000 feet (1,219 meters). The CTF virus is transmitted by a tick bite or, in very rare cases, by a blood transfusion.Tick biteTicks 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...ImageRead Article Now Book Mark Article Symptoms Symptoms of CTF most often start 1 to 14 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 (typically during fever) Lethargy (sleepiness) or confusion Nausea and vomiting Rash (may be light colored) Sensitivity to light (photophobia) PhotophobiaPhotophobia is eye discomfort in bright light.ImageRead Article Now Book Mark Article 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:Complete blood count (CBC) CBCA complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...ImageRead Article Now Book Mark Article Liver function testsLiver function testsLiver function tests are common tests that are used to see how well the liver is working. Tests include:AlbuminAlpha-1 antitrypsinAlkaline phosphata...ImageRead Article Now Book Mark Article 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 CTF.Pain relieverOver-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...ImageRead Article Now Book Mark Article Reye syndromeReye syndrome is characterized by sudden (acute) brain damage and liver function problems. This condition does not have a known cause. This syndrome...ImageRead Article Now Book Mark Article If complications develop, treatment will be aimed at controlling the symptoms. Outlook (Prognosis) CTF usually goes away by itself and is not dangerous. Possible Complications Complications may include:Infection of the membranes covering the brain and spinal cord (meningitis) MeningitisMeningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges.ImageRead Article Now Book Mark Article Irritation and swelling of the brain (encephalitis) EncephalitisEncephalitis is irritation and swelling (inflammation) of the brain, most often due to infections.ImageRead Article Now Book Mark Article Repeated bleeding episodes for no apparent causeContact 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 legsWear light-colored clothing, which shows ticks more easily than darker colors. This makes them easier to remove.Easier to removeTicks 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, ...ImageRead Article Now Book Mark Article 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.Open ReferencesReferencesBolgiano EB, Sexton J. Tickborne illnesses. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 123.Dinulos JGH. Infestations and bites. In: Dinulos JGH, ed. Habif's Clinical Dermatology. 7th ed. Philadelphia, PA: Elsevier; 2021:chap 15.Naides SJ. Arboviruses causing fever and rash syndromes. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 358.AllVideoImagesTogTicks - illustration There are many species of ticks. Of these, a large proportion are capable of carrying disease. Diseases carried by ticks include Lyme disease, Ehrlichiosis, Rocky Mountain Spotted Fever, Colorado Tick Fever, tularemia, typhus, hemorrhagic fever, and viral encephalitis. (Image courtesy of the Centers for Disease Control and Prevention.) TicksillustrationTick 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 skinillustrationAntibodies - 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. AntibodiesillustrationDeer 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 ticksillustrationTicks - illustration There are many species of ticks. Of these, a large proportion are capable of carrying disease. Diseases carried by ticks include Lyme disease, Ehrlichiosis, Rocky Mountain Spotted Fever, Colorado Tick Fever, tularemia, typhus, hemorrhagic fever, and viral encephalitis. (Image courtesy of the Centers for Disease Control and Prevention.) TicksillustrationTick 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 skinillustrationAntibodies - 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. AntibodiesillustrationDeer 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 ticksillustrationA Closer Look Lyme disease and related tick-borne infections - InDepth(In-Depth)Related Information Acute(Special Topic)Fever(Symptoms)Insect bites and stings(Injury)Incidence(Special Topic)Encephalitis(Condition)Lyme disease and related tick-borne infections - InDepth(In-Depth)Viral encephalitis - InDepth(In-Depth) Review Date: 12/4/2022 Reviewed By: Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited. © 1997- All rights reserved. A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.Content is best viewed in IE9 or above, Firefox and Google Chrome browser.
Colorado tick feverMountain tick fever; Mountain fever; American mountain feverColorado tick fever (CTF) 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.CTF is seen most often in the western United States and Canada at elevations higher than 4,000 feet (1,219 meters). The CTF virus is transmitted by a tick bite or, in very rare cases, by a blood transfusion.Tick biteTicks 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...ImageRead Article Now Book Mark Article Symptoms Symptoms of CTF most often start 1 to 14 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 (typically during fever) Lethargy (sleepiness) or confusion Nausea and vomiting Rash (may be light colored) Sensitivity to light (photophobia) PhotophobiaPhotophobia is eye discomfort in bright light.ImageRead Article Now Book Mark Article 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:Complete blood count (CBC) CBCA complete blood count (CBC) test measures the following:The number of white blood cells (WBC count)The number of red blood cells (RBC count)The numb...ImageRead Article Now Book Mark Article Liver function testsLiver function testsLiver function tests are common tests that are used to see how well the liver is working. Tests include:AlbuminAlpha-1 antitrypsinAlkaline phosphata...ImageRead Article Now Book Mark Article 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 CTF.Pain relieverOver-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...ImageRead Article Now Book Mark Article Reye syndromeReye syndrome is characterized by sudden (acute) brain damage and liver function problems. This condition does not have a known cause. This syndrome...ImageRead Article Now Book Mark Article If complications develop, treatment will be aimed at controlling the symptoms. Outlook (Prognosis) CTF usually goes away by itself and is not dangerous. Possible Complications Complications may include:Infection of the membranes covering the brain and spinal cord (meningitis) MeningitisMeningitis is an infection of the membranes covering the brain and spinal cord. This covering is called the meninges.ImageRead Article Now Book Mark Article Irritation and swelling of the brain (encephalitis) EncephalitisEncephalitis is irritation and swelling (inflammation) of the brain, most often due to infections.ImageRead Article Now Book Mark Article Repeated bleeding episodes for no apparent causeContact 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 legsWear light-colored clothing, which shows ticks more easily than darker colors. This makes them easier to remove.Easier to removeTicks 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, ...ImageRead Article Now Book Mark Article 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.Open ReferencesReferencesBolgiano EB, Sexton J. Tickborne illnesses. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 123.Dinulos JGH. Infestations and bites. In: Dinulos JGH, ed. Habif's Clinical Dermatology. 7th ed. Philadelphia, PA: Elsevier; 2021:chap 15.Naides SJ. Arboviruses causing fever and rash syndromes. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 358.