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FOOD SAFETY FACTS ON LISTERIA

What is foodborne illness?

Foodborne illness occurs when a person consumes food contaminated with pathogenic bacteria, viruses or parasites. This condition is often called “food poisoning”. Many cases of foodborne illness go unreported because their symptoms often resemble flu symptoms. The most common symptoms of foodborne illness may include stomach cramps, nausea, vomiting, diarrhea and fever.

What are Listeria monocytogenes and listeriosis?

• Listeria monocytogenes is a bacterium. It is often found in the environment, particularly in soil, vegetation, animal feed, and in human and animal feces.
• Eating food contaminated with Listeria may lead to the development of a disease called listeriosis.

What are the symptoms?

• Symptoms include: flu-like symptoms, nausea, vomiting, cramps, diarrhea, headache, constipation and persistent fever. Symptoms usually appear within 2 to 30 days and up to 90 days after consuming contaminated food.
• The very young, elderly or those with poorly functioning immune systems are the most susceptible. Flu-like symptoms may be followed by a brain or blood infection, either of which can result in death.
• A woman who develops listeriosis during the first three months of pregnancy may miscarry. If she develops listeriosis later in the pregnancy, her baby may be stillborn or acutely ill.

Where could I come in contact with listeria monocytogenes?

• Listeria monocytogenes can be found in a variety of dairy products, vegetables, fish and meat products.
• Listeria monocytogenes, unlike most other harmful bacteria, will grow slowly on foods stored in a refrigerator.
• Listeria monocytogenes can also be spread by contact with an infected product or surface, such as hands or counter tops, during food preparation.

How can I protect myself and my family?

• Keep foods out of the temperature danger zone (between 4°C and 60°C or 40°F and 140°F). Keep the refrigerator at 4°C (40°F) or colder. Refrigerate food promptly.
• Thoroughly cook or boil foods such as hot dogs and poultry products until they are steaming hot.
• Avoid raw, unpasteurised milk or foods made from it such as raw milk cheese.
• Purchase only as much product as will be consumed in 1 to 2 days.
• Wash raw vegetables thoroughly before eating.
• Wash hands before, during and after handling any type of food, especially raw meat and poultry.
• Clean all utensils, cutting boards and work surfaces with a mild bleach solution (5 ml/1 tsp. bleach per 750 ml/3 cups water) before and after using.
• Separate utensils for raw and cooked foods.
• Follow “use by” dates especially on packaged goods with a long shelf life.

If you are pregnant or have a weakened immune system

• Avoid soft cheeses such as Brie, Camembert, feta and queso blanco fresco. Other dairy products such as hard cheese, processed cheese, cream cheese, cottage cheese, or yogurt can be freely consumed during pregnancy.
• Avoid refrigerated pâtés.
• Although the risk of listeriosis associated with foods from deli counters, such as sliced packaged meat and poultry products, is relatively low, pregnant women and immunosuppressed persons may choose to avoid these foods.
• Avoid refrigerated smoked fish products unless you have cooked them, for example, in a casserole.

What are producers and processors doing to protect consumers?

• From the farm to the retail store, efforts are being made to reduce the risks associated with Listeria monocytogenes throughout the food production process.
• Individual companies and industry associations are working to develop systems that will further enhance the safety of their product.

How does the Canadian Food Inspection Agency (CFIA) protect consumers?

• The CFIA administers and enforces 12 Acts governing food safety and food inspection within Canada and at our borders.
• CFIA inspectors monitor food processing in federally registered slaughtering and processing establishments.
• CFIA inspectors also check packaging dates and labels in retail stores.
• CFIA laboratories continue to develop quick, cost-effective tests to better detect new and existing pathogens in foods and food manufacturing processes.
• In cooperation with industry, the CFIA is moving towards a modernized, science-based inspection system.

For more information on foodborne illness and safe food handling practices, visit the Canadian Food Inspection Agency website at www.inspection.gc.ca

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P0022E-01
September 2001