The Montana Department of Health and Human Services is trying to warn Montanans about Norovirus: a highly contagious and sometimes fatal disease that regularly outbreaks this time of year.

"Norovirus is something we see in Montana year-round, but it usually peaks in the wintertime," said Montana DPHHS Epidemiologist Dana Fejes. "Outbreaks of norovirus are often reported between December and April. This year has been unusually slow and we want people to know that we are in the middle of the outbreak season."

Fejes says Norovirus is always present in the population, so it’s hard to say how many cases Montana sees each year.

"Individual cases of norovirus are not reported, so we don't know the actual number of people that are ill every year. In terms of outbreaks that are reported to us though, there are 900 to 1,000 every year, but those are just the outbreak numbers... there are definitely more we don't hear about."

The typical bout of norovirus lasts for one to three days, but can be much longer for children, the elderly and those with health complications. The best way to fight the disease… is proper hand washing. Here are the recommendations from DPHHS:

Practice proper hand hygiene: Wash your hands carefully with soap and water, especially after using the bathroom or changing diapers and always before eating or preparing food. Alcohol-based hand sanitizers can be used in addition to hand washing. But, they should not be used as a substitute for washing with soap and water.

Take care in the kitchen: Carefully wash fruits and vegetables, and cook oysters and other shellfish thoroughly before eating them.
Do not prepare food while ill: People who are infected with norovirus should not prepare food for others while they have symptoms and for 3 days after they recover from their illness.

Clean and disinfect contaminated surfaces: After an episode of illness, such as vomiting or diarrhea, immediately clean and disinfect contaminated surfaces by using a bleach-based household cleaner as directed on the product label or a solution made by adding 5–25 tablespoons of household bleach to 1 gallon of water.

Wash laundry thoroughly: Immediately remove clothing or linens that may be contaminated and wash with detergent at the maximum length available cycle, then machine dry. Handle soiled items carefully—without agitating them—to avoid spreading virus.