San Diego

Mouse Carrying Potentially Deadly Virus Discovered in San Diego County

A virus that can cause deadly infections in people was found in a deer mouse in Santa Ysabel, prompting county officials to remind San Diegans how to properly clean rodent messes.

A California deer mouse captured in Inaja Memorial Park this month tested positive for hantavirus, a potentially deadly virus with no vaccine or cure, the county’s communications office said. It is the first positive test for the virus this year.

Officials with the county's vector control program routinely capture rodents to test blood samples for hantavirus. It is not unusual to find hantavirus in San Diego County, officials said, but it’s not typically found near people because it is carried by wild mice.

The virus is shed through infected rodent’s saliva, urine and feces. Humans become infected when dried particles become airborne and breathe it in, the county said. Because of this, San Diegans should avoid sweeping or vacuuming rodents’ nests or dropping and instead use a wet-cleaning” method.

Symptoms include severe muscle aches, chills, headaches or dizziness, nausea or vomiting, and difficulty breathing. 

There is no vaccine or cure for hantavirus and the disease can create deadly infections in people. About 30 to 40 percent of people who contract the virus die as a result. 

To minimize the potential for exposure to the airborne virus, the county said San Diegans should use the following steps to keep wild rodents out of their homes and workplaces:

  • 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.
  • Do not sweep or vacuum infested areas. Instead, clean up rodent droppings and urine using "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.
The County's Department of Environmental Health has more information on hantavirus here. 
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