Idaho state and local health officials are investigating a recent increase in illnesses after people drank raw milk.

Since August, more than two dozen Idahoans have reported they’ve become ill after drinking raw milk, the Idaho Department of Health and Welfare says.

At least 23 of those cases were from the bacteria Campylobacter, six of which were in kids under 12 years old. Three cases were from infections from the Shiga toxin-producing E. coli, also known as STEC.

Raw milk isn’t pasteurized, a process that involves heating the milk to kill bacteria — like Campylobacter, E. coli, Listeria and Salmonella — that can be present in raw milk.

What are the symptoms of infections linked to raw milk?

Symptoms of infections from bacteria that can be in raw milk include vomiting, diarrhea, abdominal pain, fever and dehydration. Complications can be severe, especially in people at higher risk such as young children, pregnant women, the elderly and people with compromised immune systems.

Health officials encourage people who are feeling symptoms after recently drinking raw milk to seek medical care promptly. To report an illness or get more information, officials encourage people to contact their local public health district.