In the past six months, Washington State has reported four locally-acquired hantavirus cases, three in King County and now one in Franklin County. The most recent case was in a 25-year-old woman who died on Apr. 25.

Peromyscus maniculatus (deer mouse) Image/CDC
Peromyscus maniculatus (deer mouse)

This has prompted the Benton-Franklin Health District to issue a reminder to the public about hantavirus.

People become infected with Hantavirus mainly by breathing in air contaminated with the virus, or through direct contact with Hantavirus-infected rodents, or their saliva, urine, droppings, or nesting material. In Washington State potentially infected rodents are primarily deer mice. Hantavirus is not transmitted person to person.

Symptoms usually begin 1-8 weeks after exposure to infected deer mice. Early symptoms of HPS may include, fatigue, fever and severe muscle aches.. Later symptoms include coughing and shortness of breath. Approximately 36 percent of cases result in death.

The best way to prevent Hantavirus is to avoid all wild rodents. Prevent rodents in your home/workplace by sealing up holes inside and outside your home. Trap rodents with snap traps and eliminate possible rodent food sources. When cleaning, avoid actions that raise dust such as sweeping or vacuuming in a rodent infested area.

In early April, I talked to Dr Mark Waterbury on the Outbreak News This Week Radio Show about hantavirus, his wife’s case and a theory he had concerning the transmission of hantavirus via the Cabin Air Systems of automobiles.

Since that time, Public Health- Seattle & King County addressed that issue. In an interview with  Medical Epidemiologist, Dr. Meagan Kay, this issued was discussed:

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.

Check out Dr Waterbury’s article on this topic at