May 3, 2006

First Hantavirus Case of Year Confirmed

A middle-aged woman from Big Horn County is the first person this year to have a confirmed case of hantavirus, state health officials announced Wednesday.

The woman was hospitalized but is recovering, according to Todd Damrow, state epidemiologist with the Montana Department of Public Health and Human Services (DPHHS). The department was unable to release the woman’s name because of state and federal health privacy laws.

The state Public Health Laboratory confirmed the diagnosis of hantavirus pulmonary syndrome late last week. This was the 26th case of the deadly disease reported in the state since it was first identified in 1993, according to Elton Mosher, disease surveillance specialist with DPHHS. It was the first known case in Big Horn County.

Six Montanans have died of hantavirus, which is contracted by inhaling airborne particles from dried droppings, urine, or saliva of infected deer mice. It is not contagious from person to person, nor is it known to be transmitted by farm animals, dogs, cats, or rodents purchased from pet stores.

Other counties in which hantavirus cases have occurred are Beaverhead, Cascade, Custer, Flathead, Gallatin, Glacier, Lewis and Clark, Madison, Philips, Powell, Sanders, Stillwater, Sweetgrass, Toole, and Yellowstone.

“As Montanans launch into their spring cleaning, they should be aware of the precautions they can take to help avoid hantavirus,” Damrow said. “So far in Montana the disease has been primarily associated with rural settings with lots of outbuildings and big mice populations, but it can occur anywhere infested by small rodents.

“Anything that puts you in contact with fresh rodent urine, droppings, saliva or nesting material can put you at risk for infection,” he added, “and that includes sweeping out your garage, barn, or summer vacation home.”

Hantavirus is characterized by fever, muscle and body aches, chills, nausea, vomiting, diarrhea, and fatigue. Eventually, the victim's lungs begin to fill with fluid, making breathing difficult and causing shortness of breath.

There is no specific treatment, cure, or vaccine for hantavirus, but if infections are recognized early and patients receive medical care in an intensive care unit, they are more likely to do well. In intensive care, patients are given oxygen therapy to help them through the period of severe respiratory distress.

Most cases of hantavirus have been associated with:

• Prolonged exposure to rodent-infested vacant cabins or other dwellings.
• Cleaning barns or other outbuildings.
• Disturbing rodent-infested areas while hiking or camping.
• Planting or harvesting fields.
• Living in or visiting areas where there has been an increase in rodents.

Damrow said people can help prevent hantavirus by keeping mice out of their homes and workplaces.

"You should seal all openings in your foundation, even those as small as the diameter of a pencil," he said. "Keep food, pet food, and garbage in rodent-proof containers, and keep firewood at least 100 feet from your home and raised up off the ground."

He recommended that people take the following precautions when cleaning up rodent droppings or urine:

• Do not sweep or vacuum rodent droppings or nests. This will disperse virus particles into the air, where they can be breathed into the lungs.
• Before cleaning a space, ventilate the area by opening doors and windows for at least 30 minutes to diffuse any potentially infectious material that is airborne.
• Wear rubber, latex, vinyl, or nitrile gloves.
• Spray droppings and urine with a bleach solution made by mixing 1½ cups of household bleach with one gallon of clean water. Make sure to wet the material thoroughly and wait 5 minutes for it to soak.
• Use rags or paper towels to wipe up the droppings or urine and seal them in a plastic bag before disposing of them.
• Mop or sponge the area with a disinfectant or bleach solution.
• Spray dead rodents with bleach solution and then double-bag them with all cleaning materials. Dispose of all materials through an appropriate waste disposal system.
• Wash gloved hands with soap and water or spray a disinfectant or bleach solution on gloves before removing them. Drop the gloves into a plastic bag, seal it, and discard.
• Wash hands with soap and water after removing the gloves.

If you have been exposed to deer mice and develop the symptoms mentioned above, see your doctor immediately, Damrow said. Be sure to inform him or her of possible rodent exposure.

For more information, contact your local health department or visit the Web site of the U.S. Centers for Disease Control and Prevention at http://www.cdc.gov/ncidod/diseases/hanta/hps/index.htm

Page last updated: 01/30/2012