Ontario health officials are investigating two cases of listeriosis that appear to be linked to salami recalled from stores in Ontario and Quebec about three months ago.

The salami is sold by Siena Foods based in Toronto and was voluntarily recalled by the manufacturer on Dec. 21, 2009, the Canadian Food Inspection Agency said Wednesday. The best before date on the packaged meat is May 4, 2010.

Ontario health officials say they've been told two men became ill and are recovering at home. The officials wouldn't say where the men live.

An alert has gone out to public health units across the province to watch for other possible cases.

The Ontario Health Ministry is investigating to try to determine where and when the salami was bought and whether it was sold after the recall.

Consumers can check foods in their refrigerators against a list of recalled products on the Canadian Food Inspection Agency's website.

Food contaminated with Listeria monocytogenes may not look or smell spoiled. Eating food contaminated with the bacteria may cause listeriosis, a food-borne illness.

Listeriosis can cause high fever, severe headache, neck stiffness and nausea.

Pregnant women, the elderly and people with weakened immune systems are particularly at risk. Infected pregnant women may experience only a mild, flu-like illness, but infections during pregnancy can lead to premature delivery, infection of the newborn or stillbirth.