• Listeria is a bacterium that can make people sick. Some large outbreaks of foodborne listeria have occurred involving processed foods. People that are most at risk are newborn babies, the elderly and people with weakened immune systems


  • Fever, intense headache, stomach ache and diarrhea
  • Nausea and sometimes vomiting
  • More severe symptoms may be seen in infants, the elderly and those with weakened immune systems (may result in hospitalization)
  • Death rate among cases found in adults can be as high as 30 per cent and up to 50 per cent in infants
  • The time between swallowing the bacteria and becoming sick ranges from between 3-30 days, usually within three weeks of ingesting the bacteria


  • Found in soil, standing water and the intestinal tracts of animals

  • Food contaminated with listeria

  • From the birth canal to newborns

  • People who have been sick can have the bacteria in their stool for several weeks


  • Pregnant women, children and immune-compromised people should avoid eating soft cheeses, cold cuts and smoked fish
  • Cook meats thoroughly above 74 degrees Celsius (whole poultry to 82 degrees Celsius)
  • Thaw meat in the refrigerator and not on the counter (or use microwave to thaw quickly)
  • Wash hands often when working with food (especially after working/playing with animals, handling raw meat or even packages containing raw meat).

Cases of listeriosis must be reported to your local Medical Officer of Health under the Health Protection and Promotion Act