BILLINGS — Two Montana pig farms are dealing with a virus that has killed millions of piglets since it was first detected in the United States a year ago.

David “Shorty” Hofer of North West Pork Cooperative said that pig barns at Hutterite colonies near Harlowton and Great Falls are infected with the virus that causes porcine epidemic diarrhea.

Hutterite colonies account for about 95 percent of the state’s $24.7 million hog industry.

The virus can be deadly to very young piglets. It does not affect people or other animals. There is no vaccine.

Hofer says farmers can try to prevent the spread of the disease by making sure infected fecal matter isn’t spread between barns.

Farmers hope better weather will help quell the outbreak. The virus dies quickly in warm, dry weather conditions.