OTTAWA, Sept. 19 (Xinhua) -- Authorities have linked the death of an elderly woman to the nationwide listeria outbreak in Canada, raising death toll of the disease to 18.

    Health officials in British Columbia province said Friday lab tests confirmed that the lady's listeria infection bacteria matched the national outbreak strain. She died Sept. 8.

    The outbreak originated from a meat processing plant in Torontoof the Maple Leaf Foods, where the Listeria bacterium was found embedded deep inside slicing equipment. The plant reopened a couple of days ago after being closed since Aug. 20.

    Listeriosis is a disease caused by the bacteria Listeria monocytogenes, commonly referred to as listeria.

    Listeriosis is of concern particularly to the very young, the elderly, pregnant women and to persons with poor immune systems. Illness usually occurs from two to 30 days after consuming food contaminated with the bacteria, but can occur up to 90 days later.