Food Safety Focus (7th Issue, February 2007) – Food Incident Highlight

Listeria and Individuals at Risk

Listeriosis is a foodborne disease caused by the bacteria Listeria monocytogenes. Though cases are reported infrequently in Hong Kong, a number of listeriosis outbreaks have occurred overseas in recent years. Healthy individuals rarely develop symptoms after exposure. However, the effect on high risk individuals like pregnant women, newborns, the elderly and people with compromised immunity can be severe. The infection can result in septicaemia, meningitis, encephalitis, miscarriage, stillbirth or premature birth in severe cases.

High-risk individuals should avoid foods like prepared salads, unpasteurised milk and their products, soft cheese, smoked and raw seafood, cold meats, pate, etc., as the bacteria are more frequently found in these foods. Listeria are rather unique in the sense that they can multiply in refrigerated foods that are contaminated. Good food handling techniques and proper personal hygiene should be practised to minimise the chance for infection. For further information on Listeria monocytogenes, please visit the following webpage at the CFS website.

Illustration (Left to right): prepared salad, milk and soft cheese