Most people call us because they hear scratching in the attic or find droppings in the garage. What often gets less attention is the reason rodent problems deserve urgent, professional handling in the first place: rodents carry diseases that can make people seriously ill — and the biggest risk often comes from cleaning up after them the wrong way.
Hantavirus: the one that gets headlines, for good reason
Hantavirus pulmonary syndrome (HPS) is a rare but severe respiratory disease carried primarily by deer mice and white-footed mice — both common in Sonoma, Napa, Marin, and Solano counties, especially in rural and semi-rural properties bordering vineyards, open space, and pastureland.
People don’t catch hantavirus from a bite. They catch it by breathing air contaminated with particles from rodent urine, droppings, or saliva. That’s why the classic exposure scenario is so ordinary: someone opens up a closed cabin, sweeps out a garage, or cleans a sub-level, and stirs up dried droppings into dust.
Early symptoms look like the flu — fever, fatigue, muscle aches — but the disease can progress rapidly to severe breathing difficulty. There is no specific cure, and historically roughly a third of HPS cases have been fatal. It’s rare, but it’s exactly the kind of risk that makes “I’ll just sweep it up myself” a bad plan.
The other diseases rodents bring with them
Hantavirus gets the attention, but rats and mice are linked to a longer list of illnesses:
- Salmonellosis — from food or surfaces contaminated by rodent droppings. Kitchens and pantries are common contamination zones.
- Leptospirosis — spread through water or soil contaminated with infected urine; a real concern in damp sub-levels.
- Rat-bite fever — from bites, scratches, or contact with a dead rodent.
- Lymphocytic choriomeningitis (LCMV) — carried by house mice; particularly risky for pregnant women and people with weakened immune systems.
- Plague and tularemia — rare in humans today, but both still circulate in California rodent and flea populations, which is why public health agencies monitor them.
On top of disease, rodents spread fleas, mites, and ticks, and their dander and droppings are a documented trigger for allergies and asthma — especially when contaminated material ends up inside your HVAC ductwork and gets blown through the house.
The #1 mistake: dry-sweeping or vacuuming droppings
Standard CDC guidance for small amounts of rodent contamination:
- Ventilate the space for at least 30 minutes before entering.
- Never sweep or vacuum dry droppings — it launches contaminated dust into the air you breathe.
- Spray droppings and nests with disinfectant (or a 1:10 bleach solution) until soaked, wait 5–10 minutes, then wipe up with paper towels.
- Wear gloves and a well-fitted respirator, double-bag waste, and wash hands thoroughly.
That guidance is fine for a few droppings in a shed. It is not a plan for a contaminated attic, sub-level, or duct system — those jobs involve pounds of soiled insulation, nesting material, and contaminated vapor barriers, and they call for protective equipment, proper containment, and disposal.
What a professional decontamination looks like
Our approach follows Integrated Pest Management: remove the animals humanely, then deal with what they left behind. A proper rodent cleanup includes:
- Removal of droppings, nests, and contaminated insulation
- Sanitization and odor treatment of affected surfaces (including pesticide-free options for sensitive households)
- Replacement of insulation and vapor barriers where needed
- Repair or replacement of chewed and contaminated HVAC ductwork
- Sealing every entry point so the problem — and the contamination cycle — doesn’t restart
The last step matters most: cleaning without exclusion is temporary. New rodents follow the scent trails of the old ones, and the contamination builds right back up.
When to get an inspection
If you’ve seen droppings, heard activity, or discovered a nest — or if you’re about to clean out a space that has been closed up for a season — it’s worth a professional look first. Our $350 inspection includes a full property evaluation with photo documentation of entry points and contamination, and if you move forward with the work, the fee is credited and matched — a $700 credit toward your project.
West Coast Discreet serves Sonoma, Napa, Marin, and Solano counties with unmarked vehicles and quiet, professional crews. Call (707) 978-6024 (Napa/Sonoma) or (415) 740-5170 (Marin/S.F.) to schedule an inspection.