The very recent hospital outbreak of listeriosis in Northern Ireland resulting in six cases and one death is an unfortunate reminder of the dangers of this organism for the elderly, the immunocompromised and pregnant women.
The organism, Listeria is widespread in the environment and occasionally contaminates food such as soft cheeses, cold cuts of meat, pâtés and smoked fish. It can also contaminate ready meals that have been pre-cooked and then chilled for some time before consumption. Listeria is an unusual organism in that it can grow at 5 degrees C, i.e. fridge temperatures and therefore care has to be taken with use-by dates and storage times.
In normal healthy adults the ingestion will only cause a mild infection that is flu-like and may be accompanied by diarhorea but in those with predisposing conditions may lead to serious infection.
Those with increased risk are advised to avoid these foods..