What do to if you suspect rodents are living in your car | Public Health Insider

The following is written by Hilary N. Karasz for Public Health Insider:

Here at the Insider, we’ve been talking to Dr. Meagan Kay, Medical Epidemiologist, about the cluster of hantavirus cases that we’ve had in King County over the last several months.

Meagan, what is hantavirus?

Hantavirus pulmonary syndrome (HPS) is a rare but sometimes deadly disease that people can get by breathing in hantavirus contained in the droppings or urine of deer mice. This can happen when people breathe in dust from dried deer mice urine, saliva, and droppings that contain hantavirus and get stirred up into the air. This includes exposure to deer mice nests or droppings in homes and cabins, as well as cars, trailers, or mobile homes where rodents are living. People can also get infected when they touch deer mice urine, droppings, or nesting materials that contain the virus.

Three people in King County recently got sick with hantavirus, so we want to remind the public that deer mice in the area can carry the virus. That’s why we’re urging people who live in areas where deer mice are found to inspect their cars for signs of rodents, and if they find any, to disinfect and remove droppings or nesting materials.

Where do rodents nest in cars?

Rodents nest in many different places in cars (and campers and trucks), which is a potential risk to anyone who uses the vehicle. They are more likely to nest in cars that aren’t used very often, but they can get inside any vehicle. Nests could be anywhere in the engine compartment, including in the area under the windshield wipers, between the battery and the frame, the engine air filter and near or in filter hoses and ducts of the vehicle’s passenger compartment air intake system (ventilation, heating and air conditioning), including the cabin compartment air filter. In other areas of the car, rodents may nest in the trunk and inside the spare tire compartment, throughout the passenger compartment, and inside the tailgate and headlight enclosures. Rodents get in through rust holes, vents, and ducting.

What should I wear when I’m preparing to inspect my vehicle for rodent droppings and nests, and what equipment and materials do I need to clean up what I find?

Wear disposable plastic gloves and a long sleeve shirt. If you have evidence of rodents nesting in your vehicle, you’ll want to have a bleach solution that is 1 part bleach to 9 parts water. You may also use a commercial disinfectant. Have paper towels and a garbage bag ready as well.

Should I wear a mask?

A mask is not necessary if the infestation is not extensive. For extensive infestations with piles of feces or numerous nests or dead rodents present, special precautions are recommended. In these cases, consult a qualified mechanic or automotive professional for assistance. Additional detailed instructions on hantavirus prevention for extensive infestations may be found at this Morbidity and Mortality Weekly Report.

What do I do first?

Move the vehicle into the open air – out of the garage or carport. Open the hood, doors, and trunk and leave it to air out for 20 minutes. After 20 minutes has passed, open up the engine compartment.

What do I do if I see evidence of rodents in the engine compartment?

Start by disconnecting the cables from the battery so that you don’t get shocked while cleaning up the compartment!
Using your 1 part bleach to 9 part water solution (or a commercial disinfectant) spray the materials until fully soaked. Make sure the materials are really drenched.
Let it sit for 5 minutes (or follow the manufacturer’s instructions for disinfection time).
Then using your papers towels, pick up the material and throw everything away in the garbage bag.
After you’ve thrown away the droppings and nesting materials, clean the rest of the area with additional disinfectant. Don’t reconnect the battery until the compartment is dry.
Wash the gloves with disinfectant or soap. Take off the gloves, then wash your hands with soap and water.

What do I do if rodents get inside the air ducts, or the vehicles air intake system?

Rodents can get inside the air duct system, crawl along it, and nest on the accordion style air filter or even in the hoses and ducting leading directly to the passenger compartment. Clean as described above, with a 1:9 bleach-to-water solution or commercial disinfectant, wait 5 minutes, and then remove the materials. Throw away the old filter and replace with new. Inspection, disinfection, and possible replacement of hoses, ductwork, other filters, fans, or other components of the system may be necessary if the rodent infestation is extensive: Consult a qualified mechanic or automotive professional for assistance. For extensive vehicle infestations, additional detailed instructions on hantavirus prevention may be found at this Morbidity and Mortality Weekly Report.

Should I use a vacuum cleaner or pressurized air?

No. Never sweep or use a vacuum cleaner, pressurized air, or high powered sprayers to clean up rodent droppings and nests or contaminated areas until after you’ve soaked them in a 1:9 bleach-to-water solution or commercial disinfectant. This is because the dried droppings and urine containing the hantavirus particles can get into the air, making it easier to breathe in.

How do I clean other places in the car?

Just like for cleaning the engine, wear gloves and a long sleeved shirt, soak with nesting materials and droppings with the 1:9 bleach-to-water solution or commercial disinfectant and let sit for 5 minutes before throwing away the materials in the garbage bag.

What do I do after I’ve inspected and cleaned up the vehicle?

Before taking off your gloves rinse your gloved hands in the disinfectant or 1:9 bleach-to-water-solution. Pour some of the disinfectant into the garbage bag that has the paper towels and nests you’ve cleaned up. Seal the garbage bag. Rinse your gloved hands with water, take off the gloves, throw them away, and finish by washing your hands with soap and water.

What do I do if the rodents come back?

Do everything you can to prevent rodents from taking up residence in your vehicle (as well as your garage, shed, and house). Use snap traps as a first option. Live or sticky traps are not recommended. If you haven’t used the vehicle for a while, air it out and conduct an inspection of the air ducks and filters before starting the engine.

Where can I learn more about hantavirus?

Lots of information on hantavirus and cleaning up after a rodent infestation is available at: