SALT LAKE CITY -- The Utah Department of Agriculture and Food said Monday bacteria that cause campylobacter were not found in milk samples tested last week.

Utah County health officials issued a warning against raw milk consumption last week after several cases of a severe food-borne illness were linked to products from the same dairy -- Woolsey's Dairy in Payson.

The department tested samples taken directly from a cow and a goat, the production line and from consumers.

The samples were not part of the original milking associated with the illnesses, the department said.

"We can't test milk consumed three weeks ago," spokesman Larry Lewis said.

Campylobacter is a food-borne illness that can cause diarrhea, fever and vomiting. The test results were released the same day two more cases of campylobacter were reported to the Utah County Health Department.

Joseph Miner, director of the Utah County Health Department, said 18 cases of campylobacter have been confirmed.

"That's very unusual," he said. "Normally we only get three a month."

Miner said the two cases reported Monday are likely the last strains of the outbreak.

This story appeared in The Daily Herald on page D1.