A listeriosis outbreak has caused two deaths and several infections in the country, leading to a national recall of certain plant-based milks.
What is listeria?
Listeria monocytogenes is found in soil, sewage, and untreated water. It is also found in some foods such as meats, seafood, fruits, vegetables, and dairy products.
How does the bacteria get into food?
Listeria can enter fruits and vegetables if contaminated water is used on the crops. They can also be contaminated by bacteria in the soil and by manure-based fertilizers.
Food production and processing centres can also contribute to the spread of the bacteria if contaminated water or ingredients are used there, notes Health Canada.
Lori Burrows, a microbiologist at McMaster University, adds that listeria can also get into foods or liquids if surfaces or equipment in processing plants are not adequately disinfected.
What is listeriosis?
Listeriosis is an illness caused by eating food or water contaminated with listeria.
It can also be passed from mother to baby during pregnancy.
The disease can also be spread through contact with infected animals, but it is not typically transmitted through human contact, public health officials say.
What are the symptoms ?
Listeriosis can cause vomiting, nausea, persistent fever, muscle aches, severe headache, and neck stiffness.
Symptoms of severe listeriosis can appear up to 70 days after exposure to the bacteria. In severe cases, the infection can be fatal.
Who is most at risk?
People with weakened immune systems, adults over the age of 60 and pregnant women – including their fetus or newborn – are at increased risk of complications from listeriosis, according to the Public Health Agency of Canada.