They’ve had 45 cases of "campylobacter infection" in Cache, Davis, Salt Lake, Utah and Weber counties.
They say all the cases have been linked to raw milk or cream purchased at Ropelato Dairy in Weber County.
Raw milk is from cows, goats or sheep that has not been pasteurized to kill bacteria.
That dairy's license to sell raw milk has been suspended for the time being after samples tested positive for the bacteria.
Symptoms of the illness include diarrhea, abdominal pain, fever, headache, nausea and vomiting.
They can last up to a week, and can be serious.