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Hantavirus Found in North County Mouse

San Diego County CA– (CNC) County officials are reminding people to be extra careful whenever they are cleaning mice and rodent nests after a mouse trapped in North County’s Pala Mesa area tested positive for the potentially deadly hantavirus disease.

The Vector Control Program routinely collect blood samples from deer and harvest mice and test it for hantavirus. If positive results are found, the public is notified on appropriate precautions to take, so they can continue to enjoy outdoor activities without putting themselves at risk of exposure.

The California mouse was caught in routine trapping in Pala Mesa near Old Highway 395 and was the sixth mouse that has tested positive in the county in 2014.

People have little chance of being exposed to hantavirus, even though it is common in the county, so long as mice and rodents remain in the wild — outside of people’s homes, garages, sheds and cabins.

But people can contract hantavirus if they sweep or vacuum areas where infected rodents have nested, because the disease can be inhaled if people disturb contaminated nests and rodent droppings.

“There are two important things people need to remember to help protect themselves,” said County Environmental Health Director Liz Pozzebon. “First, avoid exposure. And second, if you have to clean an area where rodents have been, do not sweep or vacuum. Use wet cleaning methods.”

Hantavirus is a rare but deadly disease that humans catch from infected rodents. About 35% of the people who contract the virus die from it. Knowing about the virus and ways to prevent catching it can help protect you and your family. Hantavirus is an airborne disease. The infection occurs when airborne virus particles from rodent droppings are inhaled. The virus does not spread from person to person.

In the western United States, deer and harvest mice are the main carriers of hantavirus. The disease does not affect the mice themselves. In San Diego County, deer mice are most found in rural areas, the desert and mountains. Avoid contact with all wild rodents, because they may also carry other diseases. Mice that commonly live with humans are house mice, not deer mice, and do not carry hantavirus.

Symptoms Of Hantavirus
When infection occurs, symptoms may appear 1 to 6 weeks after exposure to rodents or their droppings. Beginning symptoms include:
Severe muscle aches
Chills and fever
Headache or dizziness
Difficulty breathing or coughing
Respiratory problems or failure
Nausea, vomiting, or stomach pain
Low blood pressure
People experiencing these symptoms should contact their doctor immediately.

There is no treatment or vaccine for hantavirus. Medical care can help reduce the symptoms while the infected person is recovering.

At Risk Activities
Certain activities can put people at more risk for hantavirus:
Dry sweeping or using air blowers to clean structures that are not often used
Working in barns or out-buildings
Living in rodent-infested areas
Occupying places that have been empty for a long time
Using bare hands to handle grain that could be polluted with rodent droppings
Hiking or camping in rodent-infested areas

How to 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.
Wild rodents, most notably deer mice, can carry hantavirus and shed it through their saliva, urine and feces. People can breathe in the virus if infected dust from droppings and nesting materials is stirred up and becomes airborne.

People who inhale the virus 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, cure or specific treatment for hantavirus pulmonary syndrome, and the National Centers for Disease Control and Prevention (CDC) report that it kills 38 percent of the people who get it.

In 2012 an outbreak of Hantavirus hit Yosemite National Park. The National Park Service (NPS) announced a total of 10 confirmed cases of hantavirus infection in people who had visited Yosemite National Park that year. The visitors to Yosemite were residents of: California (8), Pennsylvania (1), and West Virginia (1). Three of the confirmed cases were fatal.

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