Lab tests confirmed Tuesday what Oregon health officials suspected: Raw milk from Foundation Farm near Wilsonville was contaminated with a deadly strain of E. coli.

The tests found E. coli O157:H7 in the milk, manure and the cows themselves, said Christine Stone, spokeswoman for Oregon Public Health.

Lynne Terry of The Oregonian reports at least 17 people are ill, including four children who’ve been hospitalized. Three of them are on kidney support.

Stone said multiple samples from Foundation Farm, including manure and rectal swabs from two of the cows tested positive for E. coli O157:H7. It also turned up in leftover milk.

Epidemiologists don’t always find pathogens in contaminated food because it’s never widespread in a product.

"The fact that it was found in the milk itself shows that it was probably contamination at a high level," said Dr. Katrina Hedberg, state epidemiologist.

The farm, located on 17 acres, has four Jersey dairy cows, three that are lactating. It sold to 48 households through a herd-share program in which customers bought part of the herd. Oregon health officials have interviewed most of the families.

The Salyers, who own the farm, have sold raw milk for at least a year. The Salyers have made no public comment. They’ve taken down contact information from a website and they’ve not returned calls seeking comment.