In this guide
Quick answer
Mice and rats can spread diseases including hantavirus (from deer mice in North America), salmonellosis, leptospirosis, lymphocytic choriomeningitis (LCMV) and rat-bite fever. Most infections come from breathing in dust from droppings and urine or from contaminated food and surfaces — not from bites. Never sweep or vacuum droppings: wet them with disinfectant first, then wipe them up wearing gloves.
A few mouse droppings in a cupboard can feel like a minor annoyance. But rodent urine and droppings carry germs, mouse allergens can trigger asthma, and one species in particular — the deer mouse — can carry a rare but serious virus. Here’s what the risks really are and how to protect your family.
For an overview of every common household pest, see our complete pest control guide.
Diseases spread by mice and rats
| Disease | Main carrier | How people get it | Key facts |
|---|---|---|---|
| Hantavirus pulmonary syndrome (HPS) | Deer mice, white-footed mice, cotton and rice rats (Americas) | Breathing dust contaminated by urine/droppings, often in closed sheds, cabins, garages | Rare but serious lung disease; early symptoms like flu |
| Salmonellosis | Mice and rats | Eating food or touching surfaces contaminated with droppings | Diarrhea, fever, stomach cramps |
| Leptospirosis | Rats especially | Contact with urine-contaminated water or soil, through cuts or eyes | Flu-like illness; can affect kidneys and liver |
| Lymphocytic choriomeningitis (LCMV) | House mice | Contact with urine, droppings, saliva or nesting material | Usually mild; risk in pregnancy |
| Rat-bite fever | Rats (and sometimes mice) | Bites, scratches, or contaminated food/water | Fever, rash, joint pain; treatable with antibiotics |
In the UK, the house mouse and brown rat are the main concern; leptospirosis (Weil’s disease is a severe form) and salmonella are the risks most often mentioned by the NHS and public health bodies. Hantavirus pulmonary syndrome is mainly a concern in the Americas.
Allergies and asthma
Mouse urine contains proteins that are a significant indoor allergen. Studies in US cities have found that mouse allergen exposure is linked to asthma symptoms in children, much like cockroach allergen. Removing the mice and cleaning thoroughly helps. See also Can Cockroaches Cause Asthma?
Signs you have mice or rats
- Droppings: mouse droppings are small (about 1/4 inch), dark and rice-shaped with pointed ends; rat droppings are larger (1/2–3/4 inch).
- Gnaw marks on food packaging, wood, plastic and wiring.
- Scratching or scurrying in walls or ceilings at night.
- Nests of shredded paper, fabric or insulation.
- Grease marks along walls where they run.
- A musky, urine smell in enclosed spaces.
If the noises are in your walls, follow our guide on how to get rid of mice in walls.
How to clean up droppings safely (CDC method)
Do not sweep or vacuum droppings
Sweeping and vacuuming stir germs into the air where you can breathe them in. This is how most hantavirus infections happen.
- Ventilate. Open doors and windows for at least 30 minutes before you start, and leave the area during that time.
- Wear rubber, latex or nitrile gloves.
- Spray the droppings, urine and nesting material with a disinfectant or a fresh bleach solution (1 part bleach to 10 parts water) until thoroughly soaked. Let it soak for 5 minutes (or as the disinfectant label directs).
- Wipe up with paper towels and put them in a sealed plastic bag in the trash.
- Mop or sponge the area with disinfectant.
- Disinfect items that may have been contaminated, and wash bedding or clothing in hot water.
- Remove gloves and wash your hands thoroughly with soap and water.
For heavy infestations or cleanup in closed buildings like cabins and sheds in hantavirus areas, consider a professional and wear a respirator.
When to see a doctor
Seek medical care if…
you develop fever, muscle aches (especially in thighs, hips and back), fatigue, headache, nausea or shortness of breath within 1–8 weeks after cleaning up rodent areas or being in a rodent-infested building. Tell the doctor about the rodent exposure — early care matters for hantavirus. Also see a doctor after any rodent bite.
Prevention: keep rodents out
- Seal entry points. A mouse can squeeze through a gap about 1/4 inch wide; a young rat about 1/2 inch. Use steel wool plus caulk, metal flashing or hardware cloth — rodents chew through foam and plastic.
- Store food (including pet food and birdseed) in glass or metal containers.
- Keep trash in bins with tight lids.
- Clear clutter in garages, basements and attics.
- Trim vegetation away from the house and store firewood off the ground and away from walls.
- Trap promptly at the first sign. See Best Mouse Traps.
Frequently asked questions
Can you get sick from mouse droppings?
Do house mice carry hantavirus?
Is it safe to live in a house with mice?
Sources
- Centers for Disease Control and Prevention — How to clean up after rodents
- CDC — Hantavirus
- NHS — Leptospirosis (Weil’s disease)
Health note: This article is for general information and isn’t medical advice. If you or someone in your home has symptoms such as wheezing, a persistent cough, a rash that spreads, or a fever after a bite, talk to a doctor or other qualified health professional. Read our disclaimer.
