The Arizona Department of Health Services today urged the public to take appropriate precautions when living or working in rodent infested areas, following the confirmation of the state’s first case of Hantavirus Pulmonary Syndrome (HPS) in 2005.

Health officials are currently investigating the case, in which an individual likely became infected through exposure to mouse droppings in a rural area. While most common in rural areas, HPS can occur anywhere in Arizona. A second reported case also was investigated, but has since been ruled out.

HPS is an often deadly disease that usually begins with flu-like symptoms, and may rapidly progress to respiratory failure when the lungs fill with fluid. Patients usually develop breathing difficulty approximately two to six days after onset of symptoms

“The abundant rainfall this winter may have increased the hantavirus risk in rural Arizona as wild mouse population appears to have increased ” said State Epidemiologist David Engelthaler. “Similar conditions were seen in the winter of 1993 when we had an outbreak of hantavirus pulmonary syndrome in the Four Corners Region of Arizona, Utah, Colorado and New Mexico.” Fifty-three cases of HPS were identified during that outbreak.

“The best defense against infection with hantavirus is to avoid cleaning or disturbing areas with recent rodent infestation including nests and droppings," said Engelthaler. “If you do have to clean up droppings or nests, be sure to thoroughly disinfect the area first. Be especially cautious when entering a structure, such as a summer cabin, that has been closed up. People who have been exposed to rodent droppings and who become ill with HPS-like symptoms should seek medical care."

To date, 40 cases of HPS have been reported in Arizona since 1992 (including the new case). Nine cases were fatal. Two cases were reported in Arizona last year.

Hantavirus can occur wherever the deer mouse and its close relatives live, which includes most rural areas throughout the state. Engelthaler stressed the importance of taking preventive measures to avoid contracting the disease and the Health Department issued the following

guidelines to reduce risk of contracting Hantavirus Pulmonary Syndrome:

Proper clean up methods:

• When rodent droppings or nests are found in and around the home, spray them liberally with a household disinfectant and allow them to soak for at least 15 minutes. Use disinfectants that kill viruses, such as Lysol®, or a solution of one‑part household bleach mixed with nine parts water.
• After disinfecting, wear rubber gloves and clean up the droppings with disposable materials such as paper towels, rags or mops.
• Seal all materials, droppings or nests in double plastic bags and dispose of them in the trash.
• Do not clean the droppings or nests by sweeping, brushing or vacuuming, since these methods stir up dust and increase a person's chances of inhaling the virus.

Rodent proof your home:

Rodent control:

• Control rodents inside the home by placing spring loaded "snap" traps in areas where rodents and their droppings have been observed. Bait the traps with peanut butter and/or oats and check them regularly. When rodents are caught, spray the dead rodents with a disinfectant, such as Lysol or bleach and water, then wait at least 15 minutes. Put on rubber gloves and then seal the dead rodents in plastic bags before disposing of them in a trash can. The snap traps can be disinfected and re‑used.
• In areas above 4,500 feet in elevation, any dead rodents and rodent nests should be sprayed with a pesticide to kill fleas before disinfecting or disposing the carcasses. This is to prevent flea bites and possible exposure to another disease, the plague.

For more information about HPS contact the Arizona Department of Health Services Vector Borne Disease Program at (602)364-4562.