Rodents

Mice and Rats

Mice and rats can contaminate food, chew on wires and possibly cause fires, damage structures, and most importantly, carry pathogens linked to human illness.

Should I Worry About Mice and Rats?

Rodents can be destructive, dangerous, and threaten the health of people and pets. This justifies rodent management, and why they should not be tolerated where people live, work, learn, or play.

Rodents contaminate countertops, cabinets, and food. Their urine, droppings, and corpses can contain pathogens that affect human health and contaminate every stage of the food production chain.

Whether by chewing or burrowing, rodent activities damage structures.

Rodents are known carriers of pathogens (disease-causing organisms) and components of rodent urine are a known source of allergens that can lead to asthma.

Physical Damage

Whether by chewing or burrowing, rodent activities damage structures.

Gnawing

Rodents use powerful jaws and strong teeth to chew through materials and access perceived resources. This can include:

weather stripping on doors
building materials (wood, sheetrock, etc.)
dumpster lids, and
electrical wires (particularly dangerous)
It is thought that a percentage of building fires with an unknown cause might be due to rodents chewing wires.

In heavy infestations or in places where rodents wish to enter, they can gnaw through various types of materials.

a wire with gnaw marks — Rodents chew on objects to obtain actual or perceived resources. Rodents might chew on wires because they perceive these as twigs that hold liquid or insect larva for food. Image credit: Matt Frye

a door with part of the bottom gnawed away — These wooden doors in a school show evidence of rodent gnawing, which created a large enough gap from them to fit below (1/2 inch high).

Burrowing

Norway rat burrowing can damage plant roots and ornamental plantings. Infrastructure including sidewalks, statues, and other objects can be undermined and collapse.

dead shrubs in a median surrounded by green shrubs — Norway rats can damage landscape plantings when they burrow in the soil and disturb the roots.
Photo by Matt Frye

Pathogens

Rodents are known carriers of pathogens (disease-causing organisms) transmitted to people in two ways.

Direct Transmission

Rodents can contaminate surfaces or food items with droppings, urine or dead bodies.
Cleaning up dry rodent droppings without using a mask is the primary route of exposure for one type of Hantavirus.
Norway rats have also been known to bite the young, elderly, or individuals with limited mobility, who might have food residue on their bodies during sleep.

Indirect Transmission

Rodents can host arthropod vectors (insects, ticks, and mites). Fleas, lice, and mites that feed on rodents can transmit pathogens and parasites to people and pets. Particularly, fleas that feed on rodents may acquire and transmit several serious pathogens that cause human diseases.

Allergens

Components of rodent urine are a known source of allergens that can lead to asthma.