The Connection Between Lyme Disease and Mice

Kyle Belmont's picture

Recently NPR’s Morning Edition aired a story about the potential role white-footed mice play in spreading Lyme disease. To learn what this means to New Hampshire, we sat down with Alan Eaton, UNH Cooperative Extension State Entomology Specialist.

For Eaton, the white-footed mice theory is not new. “This pattern was discovered quite a few years ago when researchers in the Northeast noticed white-footed mice and chipmunk populations peaked after a good mast year.” A mast year is a year with a large crop of tree seeds or nuts, like acorns.

While the theory is not new, Eaton doesn’t know of anyone monitoring the white-footed mouse population in New Hampshire. This lack of information prevents linking mice numbers to Lyme disease cases in the state.

Another factor to consider for Lyme disease is rainfall. Ticks do not thrive in dry weather, so last summer’s drought most likely impacted how many ticks were found during collections in New Hampshire’s southern counties.

No matter the population of white-footed mice, or the amount of rainfall, Eaton stresses the importance of checking yourself for ticks whenever you have been outside. As the snow melts, and temperatures rise above 40°F, ticks will become active. Eaton notes that “checking yourself for ticks is a powerful preventive tool.”

For more information about the white-footed mouse in New Hampshire, check out the animal info sheet from our friends at Squam Lake Natural Science Center.

The graphic in this article uses a data map created by the Center for Disease Control. Click here to learn more about reported cases of Lyme disease nationwide.