First Montana Hantavirus Case Reported for 2013

The Montana Department of Public Health and Human Services has confirmed the first case of Hantavirus infection in a Montana resident in 2013. The individual is expected to make a full recovery. The resident of Deer Lodge county is believed to have come into contact with the virus while cleaning an area that had been contaminated by rodents.

This case is one of 36 Hantavirus infection cases reported in Montana since 1993. Montana typically sees one to two cases a year, making Montana second only to New Mexico in the number of cases per 100,000 population. “Montanans should be aware of the precautions they can take to avoid Hantavirus and the rodents that can carry it,” said DPHHS Director Richard H. Opper. “People can contract the illness when they breathe in air contaminated by the virus. It is important to avoid actions that raise dust, such as sweeping or vacuuming if signs of rodents are present. Protecting yourself and cleaning correctly is essential.”

During spring and summer months more opportunitites for exposure may occur as people clean out building or recreate outdoors and come in contact with mouse and rat nesting materials.

According to Dr. Steven Helgerson, the State Medical Officer, early symptoms of Hantavirus infection include fever and muscle aches, and sometimes chills, headache, vomiting. Within a few days, symptoms progress to coughing and severe shortness of breath. The symptoms develop one to six weeks after exposure.

“Early recognition and immediate medical care are key to surviving the illness,” Helgerson said. “If someone is exposed to rodents and experiences symptoms – especially severe shortness of breath, they need to seek treatment right away. Telling your doctor about any rodent exposure will alert your physician to look closely for any rodent-carried disease, such as Hantavirus.”

The best way to prevent Hantavirus transmission is to control rodent populations in areas where one lives and works. When cleaning areas where rodents may nest, the following precautions should be followed:

  • 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
  • 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 the dust and aerosolize the droppings

More information on Hantavirus and its prevention can be found at or from CCHD’s printable fact sheet.

Get more information from DPHHS here.