Hantavirus Reminder Issued After Two Deer Mice Test Positive

Health officials are reminding all Riverside County residents to take precautions against a potentially deadly virus that’s spread by common deer mice.

Two deer mice collected last month near the Sage area southeast of Hemet tested positive for Hantavirus, county officials announced today, and the California Department of Public Health confirmed the finding.

Between 2001 and 2010, approximately 13 percent of the deer mice collected in Riverside County tested positive for Hantavirus. This is fairly consistent with the average for California, according to today’s announcement. 

To date, there are no documented human cases of Hantavirus pulmonary syndrome originating within Riverside County, the statement read. 

Of the 56 human cases identified in California since 1980, 37 percent were fatal.

According to county health officials, Hantavirus may be transmitted by inhalation of tiny droplets contaminated with the virus from deer mouse secretions such as droppings and urine.  Infectious deer mice do not appear to show any signs of illness so it is important to keep from stirring-up materials while cleaning up any mouse infested areas around homes, especially in rural areas.  Residents can take the following steps to reduce their exposure to Hantavirus:

• Ventilate the affected area the night before cleanup by opening doors and windows.

• Use rubber gloves.

• Apply household disinfectants at maximum recommended concentrations for rodents, rodent droppings, nests, contaminated traps and surrounding area and allow at least 15 minutes contact time before removal.

• Clean the affected area with a sponge or mop. DO NOT SWEEP OR VACUUM.

• Double-bag the disinfectant-soaked rodent and clean-up materials (newspaper, paper towels, etc.) securely in plastic bags and seal.

• Before removing gloves, wash gloved hands in disinfectant, and then in soap and water. Thoroughly wash hands with soap and water after removing gloves. Dispose of gloves and clean-up materials with other household waste.

The early warning signs of human infection may include fever, headache, muscle aches, vomiting and abdominal pain. These symptoms may last a few hours to several days.  As the illness progresses, the lungs fill with fluid, making breathing difficult. Respiratory failure can follow rapidly, according to county health officials.

Individuals having concerns about illness should contact their health provider.  

For more information on Hantavirus and the Vector Control Program, contact the Riverside County Department of Environmental Health in Hemet at (951) 766-9454 or www.rivcoeh.org.