Lyme (and other tick-borne) Diseases
Written by Dr. Carly Wilbur, psi Medical Director
Welcome to a very special edition of psi’s Paradigm! Are you up to date on your Lyme disease symptoms, treatments, and preventions? With the beginning of the new school year as well as a nationwide increase in tick-illnesses, know the facts!
By all accounts, the number and extent of tick-borne illnesses are increasing annually in the United States. While Lyme disease is the most recognized of these illnesses, the Centers for Disease Control (CDC) reports that seven new tick-borne germs have been identified in the US in the last two decades. And while not all cases get reported, the number of logged cases of Lyme disease has tripled since the early 2000’s. Several factors are to blame: new tick species have been identified, reforestation projects bring humans and wildlife in closer proximity, and climate change has altered the ecological nature and seasonal cycles that affect ticks and their hosts.
Nationwide, this has historically been an issue for the Northeast and Midwest regions of the United States, but the geographic area of concern is growing, and the number of counties that qualify for a “high risk” label for Lyme disease has increased 300% in 20 years.
In Ohio specifically, the incidence of Lyme has skyrocketed: Only 44 cases (in 28 counties) were reported in 2010, but that number was up to 270 cases (in 44 counties) by 2017 (the most recent published data for our state).
While not every tick encounter results in a diagnosis of Lyme disease, it’s important to recognize the symptoms that would increase one’s index of suspicion.
Erythema Migrans (EM) rash (pictured) and generalized malaise (fever, headaches, muscle pains, joint pains) within 1-2 weeks of a tick bite. If these complaints are not identified, the disease can progress within 2-4 weeks to a more disseminated form that carries the risk of central nervous system involvement (meningitis, cranial nerve palsies, eye conditions) and heart problems. Late disease, often recognized months after a tick bite, carries an even greater risk of nerve damage and prolonged arthritis.
Knowing what to look for is helpful. The Ixodes scapularis (AKA Blacklegged Tick) is tiny, and the nyph (baby) phase of the life cycle can be <3mm in size.
Certain precautions can help prevent Lyme disease:
- When hiking, walk in the middle of the path, not the tall grass.
- Use EPA-approved insect repellant spray with DEET.
- Wear long sleeves and long pants. Tuck pant legs into socks.
- Clothing and gear can be pre-treated with permethrin. After exposure, clothing can be placed in the dryer on a high heat setting.
- Wearing light colored clothing makes ticks easier to see.
- Shower off and check yourself (and your pet) thoroughly after being in tick-infested areas. Promptly remove any ticks discovered.
- Continue to check for ticks 2-3 days after outdoor activities in areas known for ticks.
- Be sure to protect your pet(s) with regular anti-tick treatments.
If a tick is discovered, immediate removal is advised.
Because NE Ohio is not currently considered an area of high endemicity for Lyme disease, the standard of care is to not start antibiotics unless certain criteria are met:
- Tick is engorged
- Tick has been in place >36 hrs
- Patient has classic EM rash at tick site.
Blood tests to confirm diagnosis are not necessary if the history and presentation are classic. EM with known exposure warrants a course of empiric antibiotic treatment.
Atypical symptoms should prompt a laboratory work-up that includes quantitative screening for serum antibodies to Lyme disease. If these are negative, no further testing is needed. Positive tests will need follow-up with Lyme immunoblot or Western blot for presence of IgM and IgG antibodies. Only with a strong response to both antibody types, can a definitive diagnosis be made.
If antibiotics are warranted, first-line agents include oral Doxycycline twice daily for 10 days or Amoxicillin three times a day for two weeks. Most clinicians will administer a single prophylactic dose of Doxycylcine if an engorged tick has been discovered.
For more info on Lyme disease symptoms, treatment, and prevention:
Center for Disease Control – Lyme Disease
More info on Dr. Carly Wilbur, psi Medical Director
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