The Canadian Food Inspection Agency is warning not to consume the Veggie Patch brand Ultimate Meatless Burger because of possible Listeria contamination.

The affected product was imported from the United States and sold in one kilogram packages with two best before dates — Jan. 12 and Jan. 17, 2013 (UPC 6 10129 08477 7).

It was distributed in New Brunswick, Newfoundland and Labrador, Nova Scotia, Ontario, and Quebec.

The importer, Costco Wholesale Canada Ltd., is voluntarily recalling the burgers. The CFIA is monitoring the recall.

So far, there have been no reports of illnesses.

Food contaminated with Listeria monocytogenes may not look or smell spoiled, according to the CFIA.

Consuming food contaminated with 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.