TORONTO (AP) — Meat tainted with a deadly bacteria in a Toronto processing plant is likely to sicken more people in the coming months, a Canadian health expert said Tuesday, a day after the government announced the death toll from the outbreak had risen to 12.

Test results announced over the weekend linked the outbreak to ready-to-eat meat tainted with the Listeria bacterium. Maple Leaf Foods has recalled 220 forms of meat products, including bologna, turkey, ham and other products — all produced at one Toronto plant.

Linda Corso, spokeswoman for the Food Safety Network, told The Associated Press that listeriosis has an incubation period of up to 90 days, meaning people may become ill in the next three months from eating meat prior to the recall — or after if they aren't aware of the recall.

"Food can look, taste and smell normal, so you won't know the infection is there weeks after you purchased the contaminated products," she said. "We also don't know the extent of the outbreak yet and it's really too soon to know now. That, coupled with the long incubation period makes this outbreak very concerning."

Listeriosis is a type of food poisoning that can be dangerous to the elderly, newborns, pregnant women and people with chronic medical conditions. Symptoms include fever, headache, stiffness, nausea, abdominal pain and diarrhea.