San Diego reports first hantavirus detection of 2025 in deer mouse
The County of San Diego reported this week the first detection of the lethal hantavirus in a deer mouse collected on January 3, in Cuyamaca Rancho State Park.
Health officials say finding hantavirus in wild rodents is not uncommon in San Diego County, there were a total of 25 cases in 2024. However, people rarely come into direct contact with infected animals because wild rodents naturally avoid humans.
While exposure to hantavirus is rare, people should be careful around wild rodents as there is no cure or vaccine for hantavirus.
Hantavirus is a rare but deadly virus that is spread by infected rodents. The infection is spread by inhaling particles from rodent droppings. The disease does not affect the mice themselves but can make people seriously ill.
Hantavirus: An interview with Dr Paul Ettestad
Symptoms of hantavirus usually develop between 1 to 8 weeks after exposure and include: severe muscle aches; chills, fever or fatigue; headache or dizziness; nausea, vomiting or stomach pain and difficulty breathing.
Contact your doctor immediately if you experience these symptoms. There is no treatment or vaccine for hantavirus infection, but medical care can help reduce the symptoms during recovery.
About 30-40% of people who contract the virus die from it.
Health authorities advise the public on preventing infection with hantavirus:
If people find wild rodents, nests or signs of them in their living spaces, they should always use “wet cleaning” methods — using bleach or other disinfectants, rubber gloves and bags. They should NOT sweep or vacuum, which could stir hantavirus into the air where it could be inhaled.
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 poop and urine.
Clean up rodent poop and urine using the “wet cleaning” methods described below.
“Wet-cleaning” Methods
Do not sweep or vacuum infested areas.
Ventilate the affected area by opening doors and windows for at least 30 minutes before starting to clean.
Use rubber gloves. Spray a 10 percent bleach solution or other disinfectants onto dead rodents, rodent poop, nests, contaminated traps and surrounding areas, then let the disinfectant stand for at least 15 minutes before cleaning.
Clean with a sponge or a mop that has been soaked in disinfectant.
Place disinfected rodents and debris into two plastic bags, seal them and discard them 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.