Harvest Mouse Tests Positive for Hantavirus

A wild harvest mouse caught in routine monitoring has tested positive for the potentially deadly hantavirus, San Diego County environmental health officials said today.

The mouse was trapped near Agua Hedionda Lagoon in Carlsbad.

Environmental health officials reminded people to protect themselves if they find signs of rodents living in homes, sheds and garages.

“People have very little chance of being exposed to hantavirus if they keep wild rodents out of their homes and workplaces,” said Environmental Health Director Elizabeth Pozzebon. “If you do find rodents inside your home, never sweep or vacuum up rodent droppings. Use ‘wet cleaning’ methods instead if you have to clean an infestation.”

Hantavirus is carried mainly by wild mice. Infected rodents shed hantavirus through their saliva, urine and feces. The reason officials say people should never sweep or vacuum up rodent droppings is because it could stir hantavirus into the air where people could breathe it in.

People who inhale the hantavirus can develop hantavirus pulmonary syndrome, which starts with flu-like symptoms but can grow into severe breathing difficulties that can kill. There is no vaccine or cure for hantavirus and the national Centers for Disease Control and Prevention report that hantavirus kills nearly 40 percent of the people who get it.

Avoid Exposure to Hantavirus:

  • Seal up all external holes in homes, garages and sheds larger than a dime to keep rodents from getting in.
  • 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 or other disinfectants 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 hands with soap and water.

For more information, contact the County Department of Environmental Health (DEH) at (858) 694-2888 or visit the DEH hantavirus Web page.





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