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Hantavirus Infection

Hantaviruses are a family of related viruses found worldwide, usually carried by rodents. There are two types of hantaviruses: New World and Old World. New World hantaviruses are usually found in the Americas and can cause hantavirus pulmonary syndrome in humans. Old World hantaviruses are usually found in Europe and Asia and can cause hemorrhagic fever with renal syndrome in humans.

Anyone can get hantaviruses, but people who have contact with rodents or rodent-infested areas are at highest risk of getting sick.

Two small white and gray rats on a hand

Hantavirus 101

Rodents can carry hantaviruses and spread them to humans in their bodily secretions, such as urine, droppings, and saliva. People become sick with hantaviruses by spending time in an environment with rodent waste and breathing in airborne particles and dust with rodents' infected bodily secretions. People may also become sick through direct contact with rodents' infected bodily secretions, or from a bite from an infected rodent. Hantavirus is not known to be spread from one person to another.

Hantavirus Pulmonary Syndrome
  • Hantavirus pulmonary syndrome is caused by New World hantaviruses, such as the Sin Nombre "Four Corners," Bayou, or Black Creek Canal virus.
  • It is spread by rodents, such as the deer mouse, white-footed mouse, rice rat, and cotton rat.
Hemorrhagic Fever with Renal Syndrome
  • Hemorrhagic fever with renal syndrome is caused by Old World hantaviruses, such as Dobrava, Hantaan, Puumala, Saaremaa, or Seoul virus.
  • Seoul virus is spread by rodents, such as the Norway rat. Having contact with Norway rats infected with the Seoul virus is the primary cause of hemorrhagic fever with renal syndrome in people living in North America.
  • It has been found in wild and pet rats around the world.
  • Rats with Seoul hantavirus will appear healthy.
  • There were several confirmed human cases of Seoul virus in the United States in 2017, including three cases in Wisconsin.

Hantavirus Pulmonary Syndrome

Early Symptoms

  • Fever
  • Severe muscle aches
  • Fatigue
  • Headaches
  • Dizziness
  • Chills
  • Nausea
  • Vomiting
  • Diarrhea
  • Abdominal pain

Late Symptoms

  • Shortness of breath
  • Coughing
  • Death in 38% of people who become sick

Signs and symptoms of hantavirus pulmonary syndrome appear one to five weeks after contact with rodents infected with the virus. Late symptoms appear four to 10 days after early symptoms.

Hemorrhagic Fever with Renal Syndrome

Early Symptoms

  • Intense headache
  • Back and abdominal pain
  • Fever and chills
  • Nausea
  • Blurred vision
  • Flushed face
  • Redness of the eyes
  • Rash

Late Symptoms

  • Low blood pressure
  • Acute shock
  • Acute kidney failure
  • Vascular leakage
  • Death in <1–15% of people who become sick, depending on the virus

Signs and symptoms of hemorrhagic fever with renal syndrome often appear within one to two weeks after contact with infected rodents. Occasionally, they may take up to 8 weeks to develop. Some people may not develop symptoms, or they may be mild.

There is currently no specific treatment for either hantavirus pulmonary syndrome or hemorrhagic fever with renal syndrome. It is important to see a doctor immediately if you have had contact with rodents and become sick with symptoms of hantavirus, as it may be helpful to treat the patient's symptoms as they develop.

Rodent control and avoiding extended contact with rodents, their nests, or droppings are key for preventing hantaviruses. Prevention measures should be taken in the home, worksite, campsite, or anywhere rodents can be present. The tips below can help to reduce the chance of becoming ill from an infected rodent:

  • Follow CDC's instructions to prevent rodent infestations: "Seal Up, Trap Up, and Clean Up."
    • Look for gaps or holes inside and outside of the home.
    • Seal up holes inside and outside the home to prevent rodents from getting inside.
    • Trap rodents around the home in order to help reduce the rodent population.
    • Clean up and remove rodent food sources and nesting sites. Store food, garbage, and pet food in containers with tight lids.
  • If you do have a rodent infestation, it is important to follow these recommendations for cleaning up after rodents.
  • Additional tips to reduce the chance of becoming ill from an infected pet include:
    • Wash your hands thoroughly with soap and water after handling your pets or areas where your pets have been.
    • Keep your small pets and their cages out of kitchens or other areas where food is served.
    • Clean pet cages, bedding, toys, and food or water containers away from areas where food is served or people may bathe.
    • Cover cuts and scratches before handling your pet.
    • For more information, see the DHS Domestic Rat Care and Human Safety webpage.

Provider Information

This is a Wisconsin disease surveillance category I disease:

Wisconsin case reporting and public health follow-up guidelines:

Hantavirus Information for Health Care Workers: The CDC webpage covering specimen submission and case definition information.

Questions about Hantavirus? Contact us!
Phone: 608-267-9003 | Fax: 608-261-4976

Wisconsin Local Health DepartmentsRegional officesTribal agencies

Last revised June 15, 2022