Does Lyme Disease Exist in Colorado Ticks?

Ticks in Colorado

Since treating those suffering from Lyme disease I am asked this question often.

According to the Centers for Disease Control website there have been only 4 reported and confirmed cases of Lyme disease in Colorado.  The Colorado Department of Public Health and Environment website does not list Lyme disease under its list of tick bourn illnesses and the Colorado State University extension website states, that “No human cases of Lyme disease have originated in Colorado.”

So why are cases of Lyme disease in Colorado not being reported or confirmed despite a growing number of practitioners diagnosing and treating Lyme disease in Colorado?   For example, last fall a young man came to me for treatment of Lyme disease.  A month earlier he had been at a concert in a park in Denver sitting on the grass near some tall weeds.   A few days after the concert he noticed an oval rash on the side of his thigh with clearing in the center (bulls eye rash).  Luckily he took a photo of the rash.  One week after the concert he developed fatigue, joint pain and fevers.  He went to the ER and they ran an antibody test that looks for exposure to Lyme disease and it was negative so they sent him home.

When antibody testing is done too early or too late in infection, false negatives may result. It has been shown that after an antibody response develops, it can wane or persist regardless of disease status.1 In a study of Borrelia-borgdorphori-infected primates, some untreated animals had antibodies develop and then disappear over time, despite persistence of infection.2 Finally, some patients fail to develop antibody responses to this infection.3 It is important to evaluate test results and the patient’s clinical history to assess the likelihood that a positive test represents the presence of the disease and that a negative test represents its absence.4 The occurrence of false negatives and false positives greatly contributes to the controversy over the diagnosis of Lyme disease.

Rocky Mountain wood tick and the American dog tick are the most common ticks in Colorado that can transmit diseases to humans.  The deer tick, which can transmit the bacteria that is associated with Lyme disease, is not as common but is present in Colorado. The most common illness transmitted by ticks here is Rocky Mountain Tick Fever, a viral infection, and less common are tularemia, powassan virus, and rocky mountain spotted fever.

About that young man that showed up with a bulls eye rash on his thigh, he had the classic symptoms of Lyme disease: fatigue, joint pain, fevers, and brain fog.  Prior to the bulls eye rash showing up he was a every healthy young man. He was treated appropriately and recovered fully.

To protect your self from tick bites it is good to cover your arms and legs as much as possible while hiking, gardening, etc.  You can treat your clothes and boots with 0.5% permethrin. DEET and picardin are effective at repelling ticks as well as lemon and eucalyptus oils sprayed on exposed body parts, except the face.  Check for ticks on yourself or your dog or cat after being outside. You can also run a lint remover (the sticky tape made for dog or cat hair removal) along your legs or arms to see if a small nymph is present.  The nymph is a tiny early stage deer tick, smaller than a pin head, but able to attach and transmit microbes to a host.

1 Leeflang MM, Ang CW, Berkhout J, Bijlmer HA, Van Bortel W, Brandenburg AH, et al.The diagnostic accuracy of serological tests for Lyme borreliosis in Europe: a systematic review and meta-analysis. BMC Infect Dis. 2016 Mar 25;16:140. doi: 10.1186/s12879-016-1468-4. Review.

2 Embers ME1, Hasenkampf NR1, Jacobs MB1, Tardo AC1, Doyle-Meyers LA2, Philipp MT1, Hodzic E3. Variable manifestations, diverse seroreactivity and post-treatment persistence in non-human primates exposed to Borrelia burgdorferi by tick feeding.PLoS One. 2017 Dec 13;12(12):e0189071. doi: 10.1371/journal.pone.0189071. eCollection 2017.

3 Kalish RA, McHugh G, Granquist J, Shea B, Ruthazer R, Steere AC.Persistence of immunoglobulin M or immunoglobulin G antibody responses to Borrelia burgdorferi 10-20 years after active Lyme disease. Clin Infect Dis. 2001 Sep 15;33(6):780-5. Epub 2001 Aug 10.

4 Craft JE, Fischer DK, Shimamoto GT, Steere AC.Antigens of Borrelia burgdorferi recognized during Lyme disease. Appearance of a new immunoglobulin M response and expansion of the immunoglobulin G response late in the illness..J Clin Invest1986;78(4):934-939.