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Ontarians Warned Not To Eat Food Products Contaminated With Listeriosis

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Ontarians Warned Not To Eat Food Products Contaminated With Listeriosis

Siena Foods Ltd. Products Have Same Genetic Fingerprint As Two Ontario Cases

Ministry of Health

Ontarians are being warned not to consume Siena Brand Prosciutto Cotto cooked ham because it may be contaminated with Listeria monocytogenes. This product would have been sold to consumers after January 11, 2010 and has best before dates of March 8 and March 22, 2010.

Dr. Arlene King, Ontario's Chief Medical Officer of Health, is issuing the warning because the genetic fingerprint of the product is a match to two listeriosis cases in Ontario. Both individuals were hospitalized but have been discharged and are now recovering.

The genetic fingerprint is also a match to a Siena Brand mild cacciatore salami that was recalled in December.

There are a higher number of listeriosis cases in the province so far this year with 14 already being reported. There are usually about 40 annually.

Ten of the 12 other cases have 10 different DNA patterns and do not appear to be linked in any way to one another while laboratory results are still pending for the remaining two cases. All cases involve adults.

National, provincial and local public health and food authorities are working together to decrease the risk to the public of further illness.

Quick Facts

  • Listeriosis is a reportable disease under the Health Protection and Promotion Act. The median incubation period is three weeks, but can occur from 3-70 days
  • Listeriosis is caused by the bacterium Listeria monocytogenes, usually transmitted through food. Those highly susceptible are newborns, the elderly, pregnant women, and persons whose immune systems are compromised. In pregnant women, infection can cause preterm delivery, spontaneous abortion, stillbirths and fetal infection
  • Listeriosis usually manifests as mild flu-like illness. More severe illness may result in meningitis and blood poisoning in newborns and adults. In pregnant women, it can cause fever and abortion.

Additional Resources


“I want to warn Ontarians not to consume these two products. They both have the exact same genetic fingerprints as two listeriosis cases in Ontario. Those most at risk include pregnant women, the very old, infants, and people with weakened immune systems.”

Dr. Arlene King

Chief Medical Officer of Health

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