Mice are in every town in America, and by some estimates, there’s one rat for every person in the U.S. They’re everywhere, and they’re destructive. They can carry fleas, lice, and ticks. Their pee, poop, hair, and saliva can contaminate your food and spread disease. If they get into your home, they can create a fire risk by chewing on electrical wires. They gnaw on structures and burrow into furniture.