Health Officials Urge Precautions After Confirming Two Fatal Cases of Hantavirus Pulmonary Syndrome

State and local health officials have urged the public to take appropriate precautions when living or working in rodent infested areas, following the confirmation of two cases of Hantavirus Pulmonary Syndrome this year. Both were fatal. One case involved a man who lived along the rural fringe of a new suburb in Maricopa County. He may have been exposed to the disease while cleaning up mouse droppings in his garage. The man, in his 60s, died in January. The other case involved a Navajo County woman who also died after contracting the disease. Hantavirus Pulmonary Syndrome 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. "As this tragedy shows us, this isn't just a Four Corners issue," said Dr. Bob England, medical director for Maricopa County Department of Public Health. "Hantavirus is carried by rodents throughout the country, including here in the Valley. It's a rare but real risk anytime you inhale dust containing rodent droppings, such as by sweeping." Heavy rains from last winter led to a surge in populations of wild mice that carry hantavirus. Increased wild mice populations are associated with increased cases of hantavirus in humans, and this may last for many months. Seven cases have occurred in Arizona in the last 13 months, the largest cluster since the 1993-1994 outbreak. House mice and roof rats are not known to carry the disease. "Similar conditions -- lots of rain followed by a dry spell -- were seen in 1993 and 1994 when we had an outbreak of hantavirus pulmonary syndrome in the Four Corners Region," said state Epidemiologist David Engelthaler. Fifty-three cases of HPS were identified in Arizona, New Mexico, Utah, and Colorado during that outbreak, including 20 cases in Arizona. To date, 46 cases of HPS have been reported in Arizona since 1992, including eight in Maricopa County. Fourteen of those 46 cases were fatal. Hantavirus can occur wherever the deer mouse and its close relatives live, which includes most rural areas throughout the state, including the suburban-fringe areas of the Phoenix and Tucson. 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: * Prevent rodents from entering the home by plugging or sealing all holes and gaps to the outside greater than 1/4-inch in diameter. Use steel wool, thick wire screen, metal flashing or cement to seal holes. * Eliminate or reduce rodent shelter around the home by removing outdoor junk and clutter, and by moving woodpiles, lumber, hay bales etc., as far away from the house as possible. * Keep the lawn trimmed and free of excess weeds and brush. * Do not make food easily available to rodents. Do not leave pet food in dishes. Dispose of garbage in trash cans with tight-fitting lids. * Wash dirty dishes promptly, and clean up spilled food immediately. Store bulk grains and animal feed in rodent-proof containers. 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.