Mouse Tests Positive For Hantavirus

A wild deer mouse trapped in North Escondido during routine monitoring has tested positive for the potentially deadly hantavirus, San Diego County vector control officials said Friday.

“Infected mice rarely pose a threat to people if they remain in the wild,” said Jack Miller, director of the County Department of Environmental Health.  “But hantavirus can be a danger if infected rodents get indoors and people come into contact with their droppings. People should never sweep up or vacuum rodent droppings or nesting materials when they find them, but use bleach solutions and sponges or mops to carefully clean up instead.”

Wild rodents, primarily deer mice, carry hantavirus. People contract the disease by inhaling dust particles containing the virus from rodent droppings and nesting materials. When the virus becomes airborne and is inhaled, it can cause hantavirus pulmonary syndrome (HPS). Symptoms, which can develop between one to five weeks after exposure, are similar to the flu but can lead to severe breathing difficulties and even death.

There is no vaccine or specific treatment for hantavirus and the National Centers for Disease Control and Prevention report the disease has killed 36 percent of all the people known to have contracted it.

The best way to prevent the disease is to keep mice out of houses, garages and sheds.

How to Avoid Exposure:

  • Eliminate rodent infestations immediately.
  • Avoid rodent-infested areas and do not stir up dust or materials that may be contaminated with rodent droppings and urine.
  • Clean up rodent droppings and urine using the wet cleaning method described below.

Use “wet-cleaning” methods to prevent inhaling the virus:

  • Ventilate affected area by opening doors and windows for at least 30 minutes.
  • Use rubber gloves. Spray a 10 percent bleach solution (2 tablespoons bleach to 1 cup of water) onto dead rodents, rodent droppings, nests, contaminated traps, and surrounding areas and let the disinfectant stand for at least 15 minutes before cleaning.
  • Clean with a sponge or a mop. Place disinfected rodents and debris into two plastic bags, seal them and discard in the trash.
  • Wash gloves in a bleach solution, then soap and water, and dispose of them using the same double-bag method.
  • Thoroughly wash your bare hands with soap and water.

For more information, contact the County Department of Environmental Health at (858) 694-2888 or visit http://www.sdcounty.ca.gov/deh/pests/hantavirus.html Or click to view: “The Airborne Menace” hantavirus video.



Gig Conaughton is a communications specialist with the County of San Diego Communications Office. Contact