Flathead City-County Health officials have confirmed hantavirus infection in a Flathead County resident.

People catch the virus by exposure to infected deer mouse droppings, urine or saliva either directly or through inhaling contaminated materials or dust. It does not spread from person to person.

Health Officer Joe Russell said the hantavirus patient lives in the Lower Valley area but may have been exposed at work or at home.

“It may or may not be occupational,” he said. “We just don’t know anything yet and we probably won’t.”

In a press release Friday, health department officials said Montana typically has one or two cases a year of this virus. This case marks the third confirmed in 2012. There have been a total of 35 hantavirus cases in Montana since 1993.

People often become infected by disturbing contaminated deer mouse nesting material while cleaning their garages and sheds.  Sweeping or vacuuming may cause the material to become airborne where it can be inhaled.  

Infection also is possible through direct contact with contaminated materials in broken skin or in the eyes or mouth.

Hantavirus begins one to six weeks after exposure with three to five days of flu-like symptoms including fever, sore muscles, headaches, nausea, vomiting and fatigue.

Within a few days, the disease rapidly progresses to severe shortness of breath.

According to Russell, the Flathead County case has not followed the typical course of hantavirus.

“This case is still kind of up in the air,” he said. “It looks like this person has been exposed to the virus based on clinical sampling. But this person does not have the hantavirus pulmonary syndrome.”

Although hospitalized, the patient was not placed in intensive care. Russell described typical treatment as breathing support. Some complications are treated with medications.

 According to the Centers for Disease Control, hantavirus infection can progress to hantavirus pulmonary syndrome, which can be fatal in up to 30 percent of patients.

Early diagnosis and immediate medical care increase the likelihood of full recovery.

Russell said Flathead County has had confirmed cases before.

“We’ve had hantavirus up in the park,” he said. “We’ve had sporadic cases but there aren’t that many reported in a year but we’ve had it here.”

Health officials advise anyone exposed to rodents or their waste who experiences symptoms to immediately seek medical treatment and advise their health-care provider about their exposure.

Prevention begins with controlling rodents in living and work areas by:

 Sealing cracks and gaps larger than 1/4 inch around window and door sills, around pipes under sinks, in foundations, attics and other areas of possible rodent entry.

 Trap mice and rats with snap traps and remove food sources.

 Keep food, including pet food, in rodent-proof containers.

Prevent exposure while cleaning by:

 Wearing rubber, latex or vinyl gloves and a mask when cleaning urine and droppings.

 Spray the urine and droppings with a mixture of bleach and water and let it soak five minutes. The recommended mixture is one part bleach to 10 parts water.

 Wipe or mop the area with a sponge or paper towel and throw away items after use.

 Wash hands thoroughly with soap and warm water after removing gloves.

 Never sweep or vacuum these areas since this puts infected materials into the air.

For additional information, visit www.cdc.gov/rodents, contact the health department at 751-8101 or visit www.flatheadhealth.org.

Reporter Candace Chase may be reached at 758-4436 or by email at cchase@dailyinterlake.com.