What Health Risks Do Mice Pose to Humans?

CDC states the deer mouse is the primary U.S. reservoir for the hantavirus strain that causes hantavirus pulmonary syndrome (HPS), and infection is chiefly by breathing in aerosolized urine, droppings, or saliva. HPS is uncommon but serious — CDC notes that a substantial share of people who develop respiratory symptoms from HPS do not survive. This is precisely why the cluster's core rule exists: never dry-sweep or vacuum droppings, since disturbing them is what releases the particles that carry the virus into the air.

Salmonellosis is a bacterial infection people get by ingesting germs from droppings, contaminated surfaces, or food; CDC lists watery diarrhea, stomach cramps, and sometimes headache, nausea, or vomiting, typically starting within about six hours to six days of exposure and lasting roughly four to seven days. Lymphocytic choriomeningitis virus (LCMV) is carried by the common house mouse; most healthy people recover without lasting effects, but CDC notes it can cause serious illness in people with weakened immune systems and in pregnant women, which is why CDC advises pregnant people avoid handling pet rodents.

Mouse droppings, urine, and dander are documented asthma and allergy triggers, particularly for children. This claim is grounded in peer-reviewed research rather than a dedicated CDC page: a National Cooperative Inner-City Asthma Study found mouse allergen detectable in the large majority of homes studied, with a meaningful share of children showing mouse sensitization associated with more severe asthma symptoms. This is presented as research context, not CDC guidance.