Deer Mice Test Positive for Hantavirus


Three wild deer mice caught in routine trapping in a rural area in Jamul have tested positive this week for hantavirus — the first to test positive for the potentially deadly virus in San Diego County in 2017.

San Diego County environmental health officials said people should always remember to protect themselves if they find rodents living in their homes, sheds and garages. Most importantly, they said, people should never sweep or vacuum up rodent nests and droppings, but use wet-cleaning methods if they have to clean.

Hantavirus is mainly carried by wild mice and is not uncommon in San Diego County. Rodents shed the virus through their saliva, urine and feces. Because of that, the virus can be stirred up into the air and inhaled if people sweep or vacuum up rodent droppings and nests.

Hantavirus can cause deadly infections in people and there is no vaccine or cure. However, people have very little chance of being exposed to hantavirus if they keep wild rodents out of their homes and workplaces.

The three deer mice were collected in routine trapping by County Vector Control along Otay Lakes Road in Jamul.

Officials said people should try to avoid exposure to wild rodents and, if necessary, use wet-cleaning methods if they have to clean an area where rodents have been.

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:

  • Do not sweep or vacuum infested areas.
  • 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