As spring cleaning gets underway, the state health department reminds Coloradans to take steps to avoid hantavirus, a rare but potentially fatal respiratory disease from a virus carried by deer mice.

People are most likely to get hantavirus by breathing in dirt and dust contaminated with deer mouse urine, droppings or saliva. More people get hantavirus in the spring and summer, often while cleaning up homes, yards and sheds.

The Colorado Department of Public Health and Environment has documented more than 110 cases of hantavirus across the state since it began tracking the disease in 1993. There has been one case of the disease in Colorado this year. The case was in a Denver resident who recovered.

“If you see deer mice in or around your home, you may be at risk for this illness,” said Dr. Jennifer House, state public health veterinarian. “The more of these mice there are, the greater the risk.” Deer mice have large ears and eyes and white undersides.

Hantavirus symptoms begin one to six weeks (average two weeks) after exposure. Symptoms include fever, chills and severe pain in the legs and back. About half of people with hantavirus also experience nausea, vomiting and diarrhea. After one to seven days of illness, the disease begins to affect the heart and lungs. Infected people may have a dry cough and difficulty breathing. Approximately one out of every three people who get hantavirus die from it.

“If you become sick with these symptoms, tell your health care provider if you have been in rodent-infested areas,” House said. “People who might have hantavirus must be hospitalized as soon as possible.”

Because there is no effective treatment for the disease, House emphasizes prevention and year-round rodent control both in and outside the home. To protect yourself from hantavirus:

• Remove wood, junk and brush piles near your home. Store firewood at least 100 feet from your house. Keep vegetation around the house well-trimmed.
• Open windows and doors for at least 30 minutes before cleaning sheds.
• Spray accumulated dust, dirt, rodent droppings and dead rodents with a mixture of bleach and water (1½ cups of household bleach to one gallon of water) or another disinfectant.
• Wear rubber, latex or vinyl gloves when cleaning.
• Never dry vacuum or sweep areas where there is evidence of rodent infestation.

To get detailed cleaning instructions or learn more about hantavirus, visit the department’s hantavirus web page.