How to Safely Clean Mouse Droppings to Avoid Hantavirus (CDC Protocol)

The CDC protocol, complete

The Centers for Disease Control and Prevention's cleanup protocol for rodent droppings is short, specific, and based on direct outbreak investigation experience. It has six steps and three things you should never do.

What you need before starting

• Rubber, latex, vinyl, or nitrile gloves
• N95 mask (or equivalent respirator)
• Eye protection (safety glasses or goggles)
• Long-sleeved clothing you can wash on hot, or disposable coveralls
• Bleach (regular household chlorine bleach)
• Spray bottle
• Paper towels or disposable rags
• Heavy-duty plastic garbage bags
• Bucket and disinfectant for mopping after cleanup

The bleach solution: 1 part bleach to 10 parts water. For a standard spray bottle, that is approximately 1.5 cups of bleach in 1 gallon of water. Mix fresh; bleach solution loses effectiveness within 24 hours.

Step 1: Ventilate the space (30 minutes minimum)

Open doors and windows to create cross-ventilation. Leave the space for at least 30 minutes before re-entering. This single step substantially reduces the airborne particle load that has accumulated, especially in spaces closed for an extended period.

Do not skip this step even if the space looks lightly contaminated. The aerosolized particles you cannot see are the actual risk. The 30-minute window is not arbitrary; it is calibrated to allow significant air exchange in typical residential spaces.

Step 2: Put on PPE before re-entering

Gloves first. Then mask (N95). Then eye protection. Then long sleeves or coveralls. Re-enter the space wearing all of this. Do not remove any PPE until cleanup is complete and you have exited the space.

The mask is the most important single item. If you have to skip something due to availability, skip the eye protection but keep the mask and gloves. The dominant exposure route is inhalation; the mask covers that.

Step 3: Spray bleach solution on all contaminated material

Thoroughly soak droppings, urine spots, dead rodents, and nesting materials with the bleach solution. Soak them until visibly wet. Then let them sit for 5-10 minutes.

This step is the entire point of the protocol. Wetting the contaminated material prevents aerosolization during cleanup. The bleach also kills the virus, but the primary mechanism that protects you is the wetting, not the disinfection. The CDC has been emphatic about this for decades: dry contaminated material releases particles when disturbed; wet contaminated material does not.

Step 4: Wipe up the material with paper towels

After the 5-10 minute soak, use disposable paper towels or rags to pick up the wetted droppings, nesting material, and disinfectant. Do not use a vacuum, broom, or anything that would re-aerosolize.

Place the used paper towels directly into a plastic garbage bag. Continue working through the contaminated area methodically, spraying ahead of where you are wiping if needed.

Step 5: Mop or sponge the entire area with disinfectant

After visible contamination is removed, clean all hard surfaces in the affected area with disinfectant. This catches contamination you could not see. Floors, countertops, cabinets, drawer interiors, shelves, anywhere droppings or urine might have spread.

For porous surfaces (rugs, upholstery, fabric items), the approach differs. Shampoo rugs and upholstery with commercial-grade steam cleaner or disinfectant. Launder fabric items in hot water with detergent. Items that cannot be cleaned with liquids (books, papers, photographs) should be placed outdoors in direct sunlight for several hours; UV exposure deactivates the virus.

Step 6: Dispose of cleaning materials safely

Tie the plastic garbage bag tightly. Double-bag if it is heavily loaded. Place in an outdoor trash receptacle that will be regularly emptied. Do not store contaminated trash bags inside your home.

Wash your gloved hands with soap and water before removing gloves. Then remove gloves and dispose of them. Wash your hands again with soap and water. Wash any reusable clothing in hot water.

The three things you should never do

The CDC protocol includes three specific don'ts that are responsible for most preventable infections.

1. Do not vacuum or sweep

Vacuuming and sweeping are the worst possible approach. Both actively aerosolize the contaminated material, creating exactly the breathing exposure the protocol is designed to prevent. Even with a HEPA-filter vacuum, the disturbance creates a cloud of particles before the filter can capture them.

If you have already vacuumed before realizing the contamination was a hantavirus risk, the CDC has specific follow-up guidance: leave the space, ventilate for several hours, then return wearing PPE and follow the standard protocol. The damage from the initial vacuuming cannot be undone, but you can minimize ongoing exposure.

2. Do not dry sweep or dust

Dusting and dry sweeping have the same problem as vacuuming. They lift particles into the air. This is also why the protocol leads with spraying liquid before touching anything. Wet contamination does not aerosolize; dry contamination does.

This is the most common mistake in routine spring cleaning of cabins, sheds, or attics. People assume that brushing droppings into a dustpan is fine. It is not. Spray first, wait, then wipe.

3. Do not handle contamination with bare hands

The dominant transmission route is inhalation, but contact transmission also occurs through cuts in skin, eyes, nose, or mouth touched after handling contaminated material. Gloves are not optional even for small amounts of cleanup.

Special cases

Vehicles and RVs

Rodents commonly nest in vehicles stored outdoors or used infrequently. The cleanup follows the same protocol with two additions. First, disconnect the battery before cleaning to avoid electrical hazards if rodents have chewed wiring. Second, check the air intake system for nesting materials; if present, replace the cabin air filter after cleanup. Running the climate system before cleanup is contraindicated because it actively aerosolizes contamination throughout the vehicle.

Cabins and seasonal dwellings

The 30-minute ventilation rule is especially important for cabins that have been closed for the winter. Open every window and door, then leave the space for at least 30 minutes. If significant rodent presence is evident (visible droppings throughout, nesting in multiple locations, smell of urine), consider professional pest control treatment before any cleanup.

Heavy infestation

For severe infestations (extensive contamination throughout a structure, dead rodents in walls or HVAC systems, evidence of multiple rodent generations), the CDC recommends professional remediation. The risk of incomplete cleanup is high, and the protective measures required scale up accordingly. Many home insurance policies will cover professional remediation for documented rodent infestations.

HVAC contamination

If rodents have accessed heating or cooling ducts, the contamination can be distributed throughout the building every time the system runs. Professional duct cleaning by a company experienced with rodent contamination is recommended. Do not attempt to clean contaminated ductwork yourself.

After cleanup: rodent control to prevent recurrence

Cleaning up after rodents is reactive. Preventing them from returning is the durable solution. The CDC's "Seal Up, Trap Up, Clean Up" framework addresses all three phases:

• Seal up: Inspect for entry points. Mice can squeeze through openings as small as a dime. Caulk gaps around pipes and wiring. Replace damaged door sweeps. Use metal screen on vents and chimney openings.
• Trap up: Snap traps positioned along walls (where rodents travel) and baited with peanut butter are effective. Glue traps and live traps are not recommended because the rodent may defecate or urinate before death, spreading contamination.
• Clean up: Follow the protocol above after any rodent activity. Repeat as needed during heavy infestation.

When to call a professional

Most routine rodent cleanup can be safely handled by following the CDC protocol. Professional remediation is appropriate when:

• The infestation is extensive (contamination in multiple rooms, evidence of long-term residence).
• Rodents have accessed HVAC systems, ductwork, or wall cavities.
• Structural damage is present (chewed wiring, insulation contamination).
• You have respiratory conditions that make PPE inadequate (severe asthma, immunocompromise).
• You are pregnant or have small children in the household and want to minimize personal exposure risk.

For people in hantavirus-endemic regions doing periodic cleanup, following the CDC protocol consistently is the durable answer. The protocol is not difficult, it does not require expensive equipment, and it works. The number of hantavirus cases each year that result from inadequate cleanup remains a meaningful share of total infections, which means improving home cleanup practice is one of the most impactful prevention measures available.