The house mouse—also known as mus musculus—is brown or grey in color, has a scaly tail, and is smaller than 7 inches in length.
House mice eat everything from plant matter to meat and can survive in naturally harsh habitats (like tundras or deserts) by seeking shelter and food within human homes.

So, how do mice get inside houses? And how quickly can they multiply? It can all be explained with a little mouse math.
Basic signs

The surest way to know you have mice is to see one. Mice are nocturnal, meaning they are active during the night, so you are most likely to spot one if you grab a midnight snack or while you’re getting breakfast in the morning. Other signs you may have mice in your home include:

1. Nibbled food – If it looks like something has been chomping down on the cookies you have on the counter or if you find the cracker box has a corner missing—you likely have mice coming in contact with your food.
2. Droppings – If you find what looks like black rice pellets in your home, especially close to food or water sources, these are probably mouse droppings.
3. Shredded Paper – Mice shred paper or other soft materials to build their nests. Discovering shredded paper bags, newspaper, or other fabrics can point to mice.

Subtraction and Addition

What exactly prompted a mouse to pick your house as its new home? It’s a combination of subtraction and addition. Mice need food and shelter to survive. When temperatures and availability of outdoor food sources drop (subtraction), mice will seek shelter and nourishment in human homes. Your home has a surplus of warmer temperatures, food, and water (addition).

“Mice can fit through a space the width of pencil,” says Jeff Crawford at A-1 Able Pest Doctors. They can also jump up to 13 inches, swim, and run across wires, cables, and ropes. You may think your home is mouse-proof, but they are extremely dexterous animals and can work their way in through the smallest of spaces.

Multiplication

Just how quickly do mice breed? Very! A female mouse can reproduce as soon as it is six weeks old. Mice can have a new litter every 3-5 weeks with each litter containing 3-11 young. If mice are nesting within the walls, basement, or attic of your home, you can quickly have an infestation.

Dangers

If mice are nesting in your home, the bacteria spores from their feces and hair can travel into your ventilation system and spread dangerous airborne bacteria through your home. Leptospirosis, salmonellosis, and other serious diseases can be contracted by humans who come into contact with bacteria carried by mice.

Prevention 

You can take the following steps to prevent mice from coming into your home:

1. Keep crumbs off kitchen counters and floors
2. Do not store food on the floor of a pantry
3. Keep pet food in sealed, airtight containers

“Exclusion is the number one way to stop rodents from entering your home,” says Crawford. Exclusion is a service offered by A-1 Able Pest Doctors where the exterior of the home is carefully inspected and potential rodent entry points are sealed.
If you have mice in your home that need to be professionally removed—or if you wish to take preventative action by scheduling an exclusion service—call A-1 Able Pest Doctors at (800) 737-8189.