Rats and mice pose numerous threats to health and property. Both species carry diseases that can spread to humans, including hantavirus, leptospirosis, typhus, infectious jaundice and bubonic plague. Rodents also carry pests such as fleas, mites, lice and ticks. Rats and mice have teeth that grow continuously. To keep teeth at the right length, both species gnaw. A gnawing rodent can chew holes in walls, damage furniture and destroy books. Rats and mice in your house can even cause fires by gnawing on electrical cords. Rats and mice eat anything humans and their pets will eat, contaminating food with urine, fecal matter and hair. According to the Indiana State Department of Health, a single mouse produces 18,000 droppings a year, while a rat produces 25,000. Mice also store food, which can attract insect pests. The old wives' tale about rats attacking babies in their cribs is based on fact. Rats are attracted by the smell of milk or food, and may bite babies.Signs of Rats and Mice in Your House Signs of rats and mice in your house include droppings. Mice have small, smooth droppings with pointed ends. Rat droppings are approximately the length of an olive pit and pellet-shaped. Other signs of rodent problems include:Burrows and nestsGnawed holes in walls, floors or ceilingsGrease marks left on walls by oily rat furHunting behavior in petsPartially eaten foodSounds in walls or at nightTracks in mud, dirt or dustUrine or musk odorsUrine stains.Preventing Rodent Infestations Denying rats and mice entry into your home is the best way to avoid rodent infestations. Unfortunately, both species can crawl through very small holes. A rat can enter a hole as small as 1/2 inch in diameter, while mice can squeeze through cracks or holes as tiny as 1/4 inch wide (about the width of a pencil). Seal holes or entranceways with material that cannot be gnawed through. Concrete, steel mesh, crushed glass and hardware cloth are good choices. Store firewood, lumber, compost or other material rodents can nest in well away from the house. Seal all human and pet foods, including wild bird seed, in secure food containers. Garbage is an abundant food source for rodents, so make sure all trash cans seal tightly as well. Clean under stoves, fridges, dishwashers and freezers regularly and clean pet food bowls every night. Fix dripping faucets and pipes to reduce access to water.Eliminating Rats and Mice Despite their reputation as rodent-killers, dogs and cats don't offer much protection against rats and mice. The rodents reproduce faster than pets can kill them, and interacting with rodents can make pets sick. Rodent control usually involves traps or poison bait. Traps may be lethal or catch-and-release. Both glue and snap traps can injure pets and children as well as rodents, so use them with care. Anticoagulant bait thins the rodent's blood until internal bleeding occurs, causing the animal to die of blood loss. Rodenticide use is best left to pest control professionals. Used incorrectly, rodent bait can poison or kill children and pets.Rodent Droppings Rats and mice in your house will leave droppings you need to clean up. Both the droppings and dropping dust can carry disease. The safest way to clean up rodent droppings is to wet the area down with antibacterial cleaners and then wipe clean with a damp cloth. A respirator can be worn as an added safety measure. Try to avoid using vacuums to clean rodent droppings. Vacuums blow dust into the air, increasing the risk of inhalation. Need More Help? If you need professional help with your project, LendingTree Home Pros can help. The good news is that LendingTree Home Pros maintains a directory of home service professionals and can match you with a home pro in your area. All the home pros listed in the LendingTree Home Pros directory are properly licensed and insured and are backed by a $10,000 money-back guarantee! Let LendingTree Home Pros help you find a pro today!