Mystery over cause of deadly disease

‘A common food source’ from Gauteng could be behind the recent outbreak of listeriosis.

Listeriosis is usually spread through the ingestion of contaminated food products most frequently with raw or unpasteurised milk and soft cheeses, but also vegetables, processed foods, ready-to-eat meats and smoked fish products.

The listeria bacterium can survive in normal temperatures associated with refrigeration (4°C). Listeria can also be transmitted from a pregnant woman to her baby during pregnancy or at the time of birth. Direct contact with the organism can cause skin lesions.

Symptoms are usually mild and may include fever, myalgia, malaise and sometimes nausea or diarrhoea. In at-risk patients, spread of infection to the nervous system can cause meningitis, leading to headaches, confusion, stiff neck, loss of balance or convulsions. How to prevent infection Unlike most other food-borne pathogens, listeria can grow in refrigerated foods that are contaminated. To prevent this, it is recommended to have fridge temperatures below 4oC; and freezer temperatures below -18oC. Therefore, those at high risk of listeriosis should avoid the following foods:

Raw or unpasteurised milk, or dairy products that contain unpasteurised milk;

Soft cheeses (eg. feta, goat, Brie); Foods from delicatessen counters (eg. prepared salads, cold meats) that have not been heated/reheated adequately; Refrigerated pâtés. There is no vaccine for preventing infection. The main preventive measure is good basic hygiene.

Use only pasteurised dairy products;

Thoroughly cook raw foods from animal sources;

Wash hands before preparing food, eating and after going to the toilet;

Wash raw vegetables and fruits. – NICD