Washington State University
Environmental Health & Safety EH&S Factsheets

Hantavirus and Rodents: Clean Up and Control

Cleanup contractors, contact EH&S or Purchasing.

Hantavirus Defined

Hantavirus is a virus that can cause an extremely rare, but serious respiratory illness called hantavirus pulmonary syndrome. This illness has been found throughout the United States for many years, but was first identified in 1993. The symptoms of hantavirus infection are similar to the flu-fever, body aches, chills and trouble breathing.

Routes of Exposure

Hantavirus is spread primarily by deer mice. It is estimated that 15% of deer mice carry the virus. Deer mice spread hantavirus in their droppings, urine, saliva and nesting material. The virus attaches itself to dust particles that can become airborne if disturbed. The virus infects humans by inhalation of the virus-contaminated dust or by close contact with contaminated material. Hantavirus can also be transmitted to humans through deer mice bites.

Risk of Exposure

The risk of acquiring hantavirus is extremely rare, even among people who are consistently exposed to mice and other rodents. The majority of exposures (70%) occur around the home.

Hantavirus poses no significant health risk to WSU employees provided that simple precautions are followed. Employees who typically clean out storage areas, barns, and outbuildings which rodents are likely to infest, or individuals who trap or work with wild rodents have the greatest potential to be exposed to hantavirus.

Rodent Control Measures

After cleanup of rodent evidence, monitor the area to determine if rodents are still infesting the area. If fresh rodent evidence is found, such as new rodent droppings or nesting material, then follow recommended rodent control measures.

  • Keep rodents out of the area by plugging, screening or covering all openings that rodents might get through (1/4 inch wide or larger). It is recommended that a pest control contractor be used. Contact EH&S or Purchasing for the name and telephone number of the current contractor.
  • Discourage rodents by eliminating food and water sources
    • Store food in containers with tight fitting covers.
    • Do not store pet food in uncovered or in open feeding dishes.
    • Fix leaky pipes.
    • Store garbage in tight containers and dispose of promptly.

Getting Assistance

Contact EH&S at 335-3041 for additional information about hantavirus or rodent clean up and control measures.

For the name and telephone number of the current pest control and cleanup contractors, contact EH&S or Purchasing.

Preventing Exposure

Precautions should always be taken whenever rodent droppings, nesting material, evidence of feeding or dead rodents are found. Never sweep, vacuum, or generate airborne dust when rodent droppings and nesting material are found.

Use only the recommended wet cleaning methods. If the rodent infestation is not severe (a few droppings in a localized area):

  • Wear latex or rubber gloves.
  • Mix a disinfectant solution of 1 part bleach to 10 parts water.
  • Thoroughly soak or spray droppings, nesting material, and dead rodents with the disinfectant.
  • Use a rag, sponge, or mop soaked in the disinfectant to clean the area.
  • Dispose of the contaminated material(excluding dead mice) into a plastic bag and seal. Put the sealed bag into a second plastic bag and seal and dispose of in the regular trash.
  • Place dead mice into a plastic bag and seal. Put the sealed bag into a second plastic bag and seal and place in a biohazard box. Contact Facilities Operations for pickup and incineration (refer to Safety Policies & Procedures S80.12 for biohazardous waste disposal).
  • Disinfect or throw away the used gloves and wash hands thoroughly with soap and hot water.

If the rodent infestation is severe (large numbers of rodent droppings in a room/building), such as found in closed, unoccupied storage areas, barns, etc.:

  • Contact EH&S to inspect the area and recommend proper cleanup and rodent control procedures.
  • Air out the area for at least 30 minutes by opening windows and doors. Make sure that adjacent uncontaminated areas are not effected when airing out the contaminated area.
  • Leave the area while it is airing out.
  • While cleaning, wear appropriate PPE, including a NIOSH-approved respirator* with HEPA filter cartridges, latex or rubber gloves, eye protection, disposable coveralls and shoe coverings or washable clothing with rubber boots.
  • Follow steps 2 through 7 listed previously.
  • Spray dirt floors with the disinfectant.
  • Dispose of one-time use PPE and clean and disinfect the respirator and rubber boots according to established procedures.

*Fit testing and training is required prior to respirator use. Contact EH&S to schedule fit testing and training.

Cleanup and Control Responsibilities

The department using and controlling an area is responsible for all required cleanup and rodent control measures. Maintenance personnel who need to enter an area with a severe infestation are not required to perform cleanup or control in such situations unless they utilize the area. The department assigned the space is responsible for cleanup and control measures prior to maintenance personnel entering the area. For severe infestations, use of a cleanup contractor is recommend.