Colorado Tick Fever

Colorado tick fever, often described as mountain tick fever or American mountain fever, is a viral infection caused by a bite from an infected Dermacentor andersoni wood tick.

This type of tick is generally referred to as the Rocky Mountain wood tick. The ticks are tiny brown parasites that are found in wooded areas and fields most frequently.

They require blood from animals and humans to stay alive. Sadly, they are also carriers of such diseases, and they can transfer these diseases on to the individuals they bite. Colorado tick fever is one of the diseases that can be spread by ticks.

While Colorado tick fever is most prevalent in the state of Colorado, Canada and the United States are restricted to this disease.

The occurrence of Colorado tick fever is most significant between February and October, with 90% of cases recorded between April and July.  You are at high risk of contracting this disease if you spend time outside in tick-infested areas.

Headaches and chills are among the signs of Colorado tick fever. These symptoms frequently begin within three to six days after a tick bite occurs. This time frame is known as the period of incubation.

They eventually go away within ten days once symptoms arise. Treatment is rarely needed, and most individuals make a complete recovery without complications.

Symptoms of Colorado tick fever

Signs of Colorado tick fever are as follows:

  • Fever (about 105°F)
  • Serious headache
  • chills
  • Light sensitivity
  • Skin tenderness
  • Weakness and fatigue
  • Vomiting
  • Muscle pains
  • Nausea
  • Loss of appetite
  • Abdominal pain
  • Faint rash

It’s crucial to keep in mind that it takes at least three days for Colorado tick fever to show symptoms. Your symptoms are likely to be triggered by another illness if you experience symptoms soon after having a tick bite.

You should talk with your doctor if you develop severe symptoms of Colorado tick fever or your symptoms do not improve within one week.


The Colorado Tick Fever (CTF) virus belongs to the genus Coltivirus and is an RNA virus.  The bite of an affected Rocky Mountain wood tick infects individuals with the CTF virus (Dermacentor andersoni).

Rocky Mountain wood ticks can be found at 4,000 – 10,000 feet above sea level in Canada and the US.

When ticks feast on the blood of a reservoir animal (an animal that has the virus circulating in its bloodstream), they become contaminated with the CTF virus.

Tiny animals, including squirrels, chipmunks, and mice, are the most significant reservoirs for the CTF virus. After the tick gets infected, it spreads the virus to several hosts (animal or human) as it feeds.

The virus is not passed from person to person except in rare cases by blood transfusion. Since the CTF virus can stay in red blood cells for many months, there should be no donation of blood or bone marrow for six months after infection.

How is Colorado tick fever identified?

Your doctor can make a diagnosis of Colorado tick fever by doing a physical evaluation and performing different laboratory tests.

Such tests can involve:

Complement fixation antibody test

This test decides if there are antibodies in the blood against the Colorado tick fever virus. Antibodies are specialized proteins that help combat harmful substances such as bacteria and viruses. If antibodies are detected against the Colorado tick fever virus, then a diagnosis of Colorado tick fever is found.

Overall blood count

This is a routine screening test that tests the body’s number of white blood cells, red blood cells, and platelets. It is a straightforward blood test that can help physicians identify the exact cause of symptoms.

Liver function test

These tests determine how well the liver functions by testing levels of proteins, liver enzymes, and bilirubin in the blood. The liver may be affected by Colorado tick fever, and thus reduced liver function may be a symptom of the disease.

How is Colorado tick fever in treated?

There is no particular treatment for Colorado tick fever. When symptoms arise, they usually go away on their own within ten days.

Acetaminophen, and other pain relief drugs like Tylenol can be used to relieve fever and muscle aches. It is necessary to get plenty of rest and remain hydrated as well.  You will need to eliminate the tick from your body as soon as possible and if you are not able to extract the whole tick from your skin, contact your doctor.

How to expel ticks from your skin?

You must never try using light matches, alcohol, or petroleum jelly to eradicate ticks. These approaches may trigger the pathogen that induces Colorado tick fever to be released by the tick.

Using fine-tipped tweezers is the safest way of removing a tick from your skin. You can eliminate the tick by doing the following:

  • Wear rubber or latex gloves if you have any. Place a hand towel or tissue over your fingers if you don’t have gloves.
  • Hold the tick as close to your skin as possible with the tweezers, and pull it up in a gentle motion. It can cause the tick to split when you pull in a twisting or jerking motion, and it would be challenging to extract the remainder of the body if this occurs. Try not to put pressure on the body of the tick.
  • Clean your hands along with the bite mark with soap and water.
  • Place the tick into a plastic bag in your freezer; take note of the date. The tick will help your doctor make a diagnosis simpler if you get sick.

What are the possible Colorado tick fever problems?

Colorado tick fever barely causes complications. Nevertheless, in some situations, the illness may lead to:

  • Encephalitis, which is the swelling of the brain tissue
  • Meningitis, an infection of the cerebral and spinal cord membranes
  • Hemorrhagic fever, which causes damage to the blood vessels and various organs

Hospitalization may be needed when complications arise.

How do I lower the risk of Colorado tick fever virus infection?

There is no vaccine in order to avoid CTF. Reducing the chance of tick bites is the best way to prevent CTF.

  • Use repellent against insects
  • Wear long sleeves and trousers
  • Avoid wooded and bushy high-grass areas
  • After spending time outdoors, conduct comprehensive tick tests

How to avoid Colorado tick fever?

You will reduce the chance of tick bites by avoiding places that are popular for being infested with ticks. Make sure to wear appropriate clothing while you are in an environment that may have ticks.

Closed-toe shoes, long trousers tucked into socks, and shirts with long sleeves are included. Wearing light-coloured clothes can also be helpful, as ticks are harder to see on dark clothing. It is effective to wear insect repellant to keep ticks away as well.

Before returning indoors, remember to check yourself, your kids, and your animals for ticks after spending some time in an environment where ticks live. Ticks that are stuck in the skin should be extracted instantly with tweezers.