Lyme Disease Risk Expanding in Kentucky: Deer Tick Study
Ticks now found across the state
Over half of counties affected
Infected ticks confirmed
Human cases are increasing
Lyme disease risk in Kentucky is increasing, as studies show expanding tick populations and evidence of infection across the state.
Researchers collected deer ticks from 794 hunter-harvested white-tailed deer, along with additional ticks from black bears and field biologists between October 2015 and January 2017.
By combining their findings with earlier data from Eisen et al. (2016), the authors found that Ixodes scapularis is now present in at least 59 counties in Kentucky.
Lockwood and colleagues concluded that deer ticks are now widespread throughout the state, including areas where they had not previously been reported.
For a broader overview, see Lyme disease overview.
Deer Ticks Now Established Across Kentucky
The study documented 41 new county records, confirming that deer ticks are established in many parts of Kentucky.
This suggests a significant geographic expansion of Lyme disease risk.
Tick populations appear to be spreading into regions previously considered low risk.
Infected Ticks Identified
Among the ticks tested, approximately 11% were infected with Borrelia burgdorferi, the bacterium that causes Lyme disease.
This finding is notable because similar studies in neighboring Tennessee failed to detect the same pathogen in large tick samples.
The presence of infected ticks confirms that transmission risk exists in Kentucky.
Human Lyme Disease Cases Are Rising
Although reported Lyme disease cases in Kentucky remain relatively low, they are increasing:
- 2006–2012: ~5 cases per year
- 2013–2016: ~14 cases per year
This represents nearly a threefold increase.
The authors did not address the possibility of underreporting, which may underestimate the true burden of disease.
For emerging patterns, see Lyme disease in emerging states.
Why This Matters
The expansion of deer ticks into new regions changes how clinicians and patients should think about Lyme disease risk.
Areas previously considered low risk may no longer be exempt.
Geography alone should not exclude Lyme disease from consideration.
Prevention Remains Essential
As tick populations expand, prevention becomes increasingly important.
Public health efforts should focus on:
- Raising awareness of tick exposure risk
- Encouraging early recognition of symptoms
- Promoting protective measures in outdoor settings
For prevention strategies, see Lyme disease prevention.
Clinical Takeaway
Lyme disease risk is expanding in Kentucky, with deer ticks now established across much of the state.
Infected ticks have been identified, and reported human cases are rising.
Clinicians and patients should remain alert to Lyme disease—even in regions previously considered low risk.
Related Reading
References
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
I apologize for the double message. 2 weeks ago, my daughters and dog and I got mobbed by deer ticks in Woodford Co. I am curious to see how widespread incidence of Lyme had been found to be.
The number of deer ticks carrying disease continues to grow in include Colorado. Doctors disagree on how many. We do not have enough entomologist with boots on the ground in Colorado to understand how many.
This is referring to Woodford County, Kentucky, not Colorado.
Thanks for the clarification.
My husband pulled a tick off his side yesterday in Franklin County Ky.and by evening had a palm sized circular red rash around bite area. No history of tick bite allergy prior. Doc offices closed so I made him go to urgent treatment center where nurse practioner was mostly unconcerned but did give him a prophylactic one time dose of Doxycycline. Tonight rash is larger and he is nauseated. No fever or aches.
A single 200 mg dose of doxycycline has been advised for a tick bite and not a rash. I encourage anyone with a rash the size of a palm to get a second opinion.
Diagnosis of tick-borne disease is no walk in the park. Anyone pulling a tick off themselves is well advised to keep the tick. If you have the tick, testing is relatively easy and inexpensive. Be proactive by wearing a tick repellent designed specifically for ticks, and talk to your friends and neighbors about being tick aware. Stay safe out there!