You can get Lyme disease without ever leaving your house. Does that statement surprise you, knowing that Lyme disease is transmitted by the bite of an infected blacklegged tick? “Okay,” you say, “I get it. A tick can be accidentally carried inside on someone’s clothing or on a pet and can then bit an occupant who was never outside.” Sure, that can happen. But what if I told you that an elderly woman who lives alone without pets and never leaves her house could conceivably get Lyme disease, just as if she had been hiking in the woods?

Here’s your clue, from a recent article in the Washington Post: “Twice in the same week, Lois Wood woke to find ticks crawling over her bare leg in her New Hampshire home. A few nights later she spotted a mouse running across her bed.” Aha!

MICE CAN BE CARRYING TICKS INSIDE

People understand that ticks are a threat when it comes to Lyme disease but few people understand the role mice play in Lyme transmission. The ticks that carry Lyme disease feed on multiple host animals during their lifetime. As immature ticks, they feed on small rodents, mainly the white-footed mouse, sometimes called the deer mouse. In fact, the newly hatched ticks first pick up the Lyme bacterium from already infected mice. Research shows that 40 to 90% of white-footed mice carry the bacterium that causes Lyme disease, acting as reservoirs. Blood-feeding ticks are required to transmit the disease. As the ticks grow, they feed on and infect larger host animals, eventually feeding on deer…or people, if convenient.

The blacklegged ticks (deer ticks) that transmit Lyme are very small ticks, even as adults. If a white-footed mouse enters your house, it can be carrying dozens of larval ticks that are only the size of poppy seeds. Since any stage of the blacklegged tick can transmit Lyme disease, your family could be at risk if one of these ticks is infected and attaches to feed.

LYME-INFECTED MICE LIVE IN OUR HOMES

This disease transmission scenario is even more likely today than it was 20 years ago because white-footed mice have moved into our homes like never before. Used to be these were outside mice, not to be confused with our common house mouse which lives almost exclusively indoors. But recently, white-footed mice have been shown to be almost as common indoors as house mice, and in some areas more common. And when white-footed mice live in your home, they are much more likely to travel from inside to outside and back, which means they can easily pick up ticks.

According to a representative of Bell Labs, which manufactures mouse bait, mice used to seasonally enter homes primarily in the fall and winter months in New England, but now it’s a year-round problem. Warmer winters mean that more mice survive. West Nile virus has killed birds of prey so more mice survive, and years with a bumper crop of acorns mean more mice survive. More mice means more infected ticks survive as well.

Now that you know what you know, hopefully you agree that controlling mice in your house and yard is more important than ever? And mice are not just a seasonal concern anymore. Give Colonial Pest a call!

For more information:

• What Do Mice in My Yard Have to Do With Lyme Disease?
• Deer Mice – The Other Indoor Mice
• Black-legged Tick Numbers Growing in New Hampshire

Photo Credit: Colby Gutierrez-Kraybill