Hantavirus: Staying Safe From Deer Mice in West Michigan

Hantavirus in Grand Rapids, Michigan

Hantaviruses are a family of viruses that can cause serious illness in people. In the United States, the most serious is hantavirus pulmonary syndrome (HPS) — a lung illness that can become life-threatening. It is rare, but it matters here in West Michigan because the virus is carried by the deer mouse, and our long, cold winters send mice looking for shelter in homes, cabins, sheds, barns, and garages around Grand Rapids and Kent County. The good news: a few safe-cleaning habits and basic rodent control dramatically lower your risk.

How people get hantavirus

In the U.S., the hantavirus that causes HPS is carried and spread by the deer mouse. People become infected through contact with infected rodents and their urine, droppings, saliva, and nesting materials.

The main way people get infected is by breathing in air contaminated with the virus. This can happen when fresh rodent urine, droppings, or nesting materials are stirred up into the air — for example, by sweeping or vacuuming an area where mice have been. Rodent bites can also spread it, but bites are rare.

Two reassuring points:

• The hantavirus that causes HPS in the U.S. does not spread from person to person. (One exception worldwide is the Andes virus in South America, which can rarely spread between people through close contact.)
• Some hantaviruses elsewhere in the world cause a different illness called hemorrhagic fever with renal syndrome (HFRS), but HPS is the form seen in the United States.

Who is at risk

Anyone who comes into contact with rodents that carry hantavirus is at risk. Exposure can happen in homes, workplaces, cabins, sheds, barns, or campsites where rodents are present.

In our area, think about the places mice like to hide: a closed-up cottage on a Michigan lake, a backyard shed or barn, a garage, a basement, or a hunting or fishing cabin opened up after sitting empty over winter.

Symptoms of HPS

Symptoms usually begin 1 to 8 weeks after contact with infected rodents.

Early symptoms are flu-like and include:

• Fever
• Fatigue
• Muscle aches — often in the thighs, hips, back, and shoulders

Some people also have headache, dizziness, chills, and stomach symptoms such as nausea, vomiting, or diarrhea.

Late symptoms appear about 4 to 10 days after the early symptoms, including:

• Coughing
• Shortness of breath, as the lungs fill with fluid

At this stage HPS can become severe and life-threatening. If you develop trouble breathing after being around rodents, get medical care right away — call 911 for severe shortness of breath.

Treatment

There is no specific cure or antiviral treatment for hantavirus. Care is supportive, which means treating the symptoms and supporting the body while it fights the virus. Severe HPS cases may require intensive care with oxygen or breathing support at a hospital such as Corewell Health, Trinity Health Grand Rapids, or University of Michigan Health-West.

There is no vaccine available to prevent hantavirus in the United States. That makes early recognition and prompt medical care important — they improve outcomes. Tell your provider if you have had recent contact with rodents or cleaned up droppings or nests.

Prevent it: keep rodents out

Prevention focuses on rodent control — removing the mice and what attracts them:

• Seal holes and gaps where rodents can get inside your home, cabin, or shed.
• Set traps to reduce rodents already indoors.
• Store food in rodent-proof containers — and don’t forget pet food, which is a common attractant.

Clean up droppings and nests the safe way

This is the most important habit. When cleaning rodent droppings, urine, dead rodents, or nests, do not sweep or vacuum — that sends the virus into the air you breathe. Instead:

• Ventilate the area first — open windows and doors and let it air out before you start.
• Wear gloves.
• Wet the materials with a disinfectant or bleach solution before wiping them up, so dust isn’t stirred into the air.
• Wipe up the dampened materials, then seal and dispose of them.

After any rodent exposure, watch your health. Seek medical care promptly if flu-like symptoms develop — and especially if you have trouble breathing. Call 911 for a breathing emergency.

For questions about rodents and home cleanup in our community, the Kent County Health Department is a helpful local resource. If you don’t have a regular doctor, Cherry Health offers primary care across Grand Rapids.