Hantaviruses infect rodents around the world. Many species can cause illness in people including hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). The virus is in the saliva, feces and urine of infected rodents and anyone who comes into frequent contact with rodents or their droppings are at risk.

HFRS is primarily seen in Europe and Asia and results in kidney failure and bleeding disorders which are usually not seen in individuals with HPS.

HPS occurs in the United States. The disease can lead to severe respiratory failure and shock. HPS was first recognized in 1993 and 366 cases have been identified in the U.S. as of June 2004.

Hantavirus syndromes are reportable to the Iowa Department of Public Health by Iowa Administrative Code 641 IAC 1.


Symptoms first appear between a few days to six weeks after contact with the virus and include a flu-like illness with any of the following signs:

  • Fever
  • Muscle and body aches
  • Chills
  • Cough
  • Headaches
  • Nausea
  • Vomiting
  • Diarrhea
  • Dizziness
  • Fatigue

The lungs may then begin to fill with fluid, making breathing difficult. Once this phase of illness begins, the disease can progress rapidly and may result in severe respiratory failure and shock. If you have been exposed to rodents and experience these symptoms, you should contact your health care provider immediately.


The virus is carried in wild rodents such as deer mice. Rodents carrying the virus do not show any signs of illness. People become infected after breathing in airborne particles contaminated with urine, droppings or saliva from infected rodents. Disease transmission can also occur if dried materials contaminated by rodent feces or urine are disturbed and are directly introduced into broken skin or the eyes, nose, or mouth. Person-to-person spread is not reported in the U.S.

Risk Factors

Anyone whose occupational or recreational activities bring them into frequent contact with rodents or their droppings is at an increased risk of contracting this disease. Most cases have been associated with occupying rodent-infested vacant dwellings, cleaning rodent-infested outbuildings or living in areas where there has been an increase in the number of rodents.


The best way to prevent this disease is by eliminating or minimizing human contact with rodents. The following precautions should be taken when cleaning rodent-contaminated areas:

  • Clean rodent droppings using a wet method rather than a dry method as this will decrease the amount of dust produced.
  • Open windows or allow areas to air out for 24 hours for better ventilation before cleaning.
  • In areas of heavy rodent infestation, gloves, dust masks, long sleeves and protective eyewear should be worn to prevent exposure.
  • Floors, countertops, cabinets and other surfaces should be cleaned with a 1:10 bleach solution.

The following precautions should be taken to decrease rodent infestations and contact with rodents:

  • Clear brush and garbage from around building foundations to decrease the availability of rodent nesting materials.
  • Seal all entry holes ¼ inch wide or wider with lath screen or lath metal, cement, wire screening or other patching materials, inside and out.
  • Elevate hay, woodpiles and garbage cans at least one foot off the ground to eliminate potential nesting sites and keep all wood piles at least 100 feet from the house.
  • Live trapping of rodents is not recommended. Instead, use an EPA-approved rodenticide with bait under plywood or plastic shelter around baseboards.
  • Clean all food preparation areas and store all food in rodent-proof containers.
  • Do not leave open bowls of pet food outside and discard any uneaten food properly at the end of the day.


No specific treatment for this disease is available but early recognition and treatment improves the prognosis. Thus, anyone with rodent exposure that is suffering from the above symptoms should contact their health care provider immediately. In severe cases, admission into an intensive care unit for respiratory support and oxygen therapy may be necessary. Even with aggressive treatment, more than half of hantavirus cases are fatal.


There was one case of hantavirus reported in Iowa in 2021.  

For more detailed information and statistics on all notifiable diseases, please see our current annual report located in the reports section of the CADE homepage.

Additional Resources