Second Case of Hantavirus in Cascade County

Montana Department of Public Health and Human Services confirmed a second case of Hantavirus Pulmonary Syndrome (HPS) in a Cascade County resident for 2012. This will be the fourth confirmed case in Montana so far this year.  Cascade City-County Health Department (CCHD) strongly urges residents to take steps to protect themselves from Hantavirus.

“Our thoughts are with those who have been affected by Hantavirus.  It is a very serious illness that is present in the environment and residents must take steps to protect themselves.” said Alicia M. Thompson, Health Officer.  “For your safety, take all recommended steps to control rodent populations and clean up rodent waste properly.  If you have been around rodents and start to exhibit symptoms is it crucial to seek medical care immediately and let your provider know you have been exposed to rodent waste.”

Hantavirus is carried by infected deer mice and can be passed on through their urine, saliva, or droppings.  The percentage of infected deer mice is highly dependent on environmental factors and can vary greatly between seasons.  Because Cascade County has recently seen two cases, it is likely that other infections could occur if people don’t take steps to protect themselves. Common tasks such as sweeping and moving boxes can disturb areas that have dried saliva, urine, or droppings from infected deer mice. As infected material is moved around, tiny particles with the virus in them get kicked up into the air. It is these tiny particles that can make you sick when they are breathed in or get into your eyes, mouth or broken skin.

Symptoms can begin one to six weeks after being exposed to the virus. The illness typically starts with 3-5 days of “flu-like” symptoms including fever, sore muscles, headaches, nausea, vomiting and fatigue.  Within a few days the illness rapidly progresses to severe shortness of breath.

Early diagnosis of Hantavirus and immediate medical care increase the likelihood of a full recovery.  Individuals exposed to rodents or their waste who experience symptoms should immediately seek medical treatment and notify their provider that they have been around rodents or rodent wastes. Providing this information to your provider will help him or her to look closely for any rodent-carried disease, such as Hantavirus.

The best way to prevent Hantavirus transmission is by controlling rodent populations in areas where you live and work.

  • Seal up cracks and gaps in buildings that are larger than 1/4 inch, including window and door sills, under sinks around the pipes, in foundations, attics and any rodent entry hole.
  • Trap indoor rats and mice with snap traps, and remove rodent food sources.
  • Keep food (including pet food) in rodent-proof containers.

If you find places where rodents have nested, or if you find rodent droppings or waste, follow these steps to help to prevent exposure to Hantavirus while cleaning:

  • Wear rubber or plastic gloves
  • Thoroughly spray/soak area with a disinfectant or mixture of bleach and water to reduce dry dusty conditions in the area being cleaned (visit or call 454-6950 and ask for a Public Health Nurse for specific mixing instructions)
  • Wipe or mop the area with a sponge or paper towel (throw away items after use)
  • Wash hands thoroughly with soap and warm water after removing gloves
  • Never sweep or vacuum in these areas as this can stir up dust and aerosolize the droppings

More information on Hantavirus and its prevention can be found at or by calling 454-6950 and asking to speak with a Public Health Nurse.