Mice and ticks are linked, but no study shows that mouse control lowers Lyme risk. The evidence points elsewhere.
This guide covers what mice do for ticks and what the trials found. It also covers what lowers your risk in Westchester, and where the research stops.
How Mice Feed Ticks
The white-footed mouse is the best-known Lyme host. The Cary Institute says it infects between 40% and 90% of feeding larvae.
Larvae hatch free of infection, per a PNAS paper from the same research group. They pick up the bacterium from hosts like mice. Adult ticks feed mostly on larger mammals such as deer.
Nymphs cause most Lyme cases, according to a review in PMC. That is why nymph numbers get so much attention.
The Two-Year Acorn Chain
Cary Institute researchers found a pattern in Millbrook, New York. A large red-oak acorn crop predicts more nymphal ticks two years later.
Acorns feed mice first. A strong mouse year raised next-year nymph numbers by about 40%, per the PNAS paper.
One catch. The same paper says no red-oak acorn crop has occurred at its sites since 2019. The pattern may not apply to a yard or house.
More mice also do not reliably mean a higher share of infected nymphs. PNAS reports that infection rates in nymphs were not tied to mouse numbers.
What Happened When Researchers Cut Mouse Contact
Several trials treated mice to cut tick numbers. The results split. Nymphs fell in some trials, but people did not clearly benefit.
| Study | Where | What they did | Ticks | People |
|---|---|---|---|---|
| Tick Project, 2022 | Dutchess County, NY | Bait boxes that coat mice with tick killer | 53% fewer forest nymphs | No effect on human tick-borne disease cases |
| Hinckley et al., 2021 | Connecticut, 622 households | Rodent-targeted bait boxes | No evidence of fewer ticks near homes | No evidence of fewer tick-borne illnesses |
| Daniels et al., 1991 | Westchester County, NY | Permethrin-treated cotton for mice | No measurable drop in nymphs or infected ticks | Not reported |
| Stafford, 1991 | Connecticut | Treated mice | Ticks on mice fell 37% and 92%, but host-seeking nymphs and adults did not fall significantly | Not reported |
Early Massachusetts work looked better. A 1987 study found mice at treated sites carried about a tenth as many ticks. Later New York and Connecticut trials did not repeat that.
A CDC review calls rodent-targeted methods "promising," with concerns about results across habitats.
Notice the Westchester result. A 1991 trial in this county found no drop in nymphs.
Does Trapping Mice in Your House Help?
No study measured it. We found no trial that links household mouse control to tick numbers or Lyme cases.
The trials above used forest and yard plots. They did not test houses.
Ticks also do not set up indoors. Clemson Extension says wood ticks do not establish populations indoors. The CDC says pets can carry ticks into your home.
Control mice for mouse reasons: droppings, gnawing and wall noise. Our mice in walls guide and mouse exterminator cost guide cover that.
What Lowers Tick Risk Where You Live
The CDC says many people with Lyme are exposed in their own yards or neighborhoods. Personal steps and yard habits carry the proof.
Tick Defense Checklist
How to use this: Tick every step you already do. Press the button to see what is still open. The steps come from CDC and county health guidance.
General guidance only. Talk to a doctor about any tick bite or rash.
Westchester County Health says to bathe within two hours. It also says to tumble-dry clothes 10 minutes on high heat. NYSDOH says blacklegged ticks usually wait on plants no higher than 18 to 24 inches.
Tick & Rodent Control · Scarsdale & Westchester
Mice in the House or Ticks in the Yard?
Our tick and mosquito and rodent control partners handle both. Pristine Pest connects you with licensed providers.
Call (877) 938-6799Yard Sprays and Bait Boxes: What the Data Shows
A Connecticut trial of a bifenthrin yard spray cut questing ticks by 63%. It found no difference in human tick encounters or tick-borne illness.
That matches the Tick Project result. Fewer ticks in the yard did not clearly mean fewer illnesses. Authors suspect people meet ticks elsewhere, which is a guess.
Pets differ. The Tick Project found lower tick-borne disease in pets.
Read our yard tick treatment evidence review and the Scarsdale tick yard treatment guide.
Rodent Control Without Poisoning Pets and Wildlife
If you do hire for mice, ask about method. The EPA says pets and wildlife can be poisoned by eating rodents that took poison.
Cornell reports over 325 wildlife rodenticide poisonings in New York from 2012 to 2024. The EPA advises prompt removal of dead rodents.
Westchester Lyme Numbers
Westchester County reported 1,311 Lyme cases for 2023. These are lab-based probable cases, and the counting method changed in 2022.
Do not compare that figure with earlier years. We found no published county count for 2024 or 2025.
When to Call a Professional
Call for mice you can hear or smell, for droppings, or for gnawing. Call about ticks if your yard backs onto woods or stone walls.
Pristine Pest is a referral service. We connect you with licensed providers. Our rodent control page and tick and mosquito page explain each.
Frequently Asked Questions
Do mice cause Lyme disease?
Mice do not cause it. Ticks carry the bacterium. The Cary Institute says the white-footed mouse infects between 40% and 90% of feeding larvae, which makes it a key reservoir.
Will getting rid of mice reduce Lyme risk in my yard?
No study shows that. Rodent-targeted trials cut nymphs in some places but did not clearly reduce human illness. The Tick Project found 53% fewer forest nymphs and no effect on human cases.
Do mice bring ticks into the house?
We found no CDC, NYSDOH or university source that names mice as a significant route. The CDC says pets can carry ticks into the home. Clemson Extension says wood ticks do not establish populations indoors.
What is the acorn and tick connection?
The Cary Institute found that a large red-oak acorn crop predicts more nymphal ticks two years later, because acorns feed mice first. No red-oak crop has occurred at its sites since 2019.
How do I lower my tick risk?
Use EPA-registered repellent, treat clothing with 0.5% permethrin, check for ticks, shower soon after being outdoors, and keep a 3-foot wood-chip or gravel barrier. The CDC lists these steps.
How many Lyme cases does Westchester report?
Westchester County reported 1,311 Lyme cases for 2023. These are lab-based probable cases, and the counting method changed in 2022, so do not compare with earlier years.
Is rodent poison safe if I have pets?
The EPA says pets and wildlife can be poisoned if they eat rodents that consumed certain poisons. Ask any provider which method they use and how they remove dead rodents.
Does Pristine Pest treat ticks or mice?
No. Pristine Pest is a referral service. We connect Westchester homeowners with licensed providers. Call (877) 938-6799 to be matched.