Listeriosis

What is listeriosis?

Listeriosis isn't a common infection. It's caused by bacteria called Listeria monocytogenes, which is often found in soil and is present in most animals. It's transmitted to humans through contaminated food, and common examples are:

• Prepacked salads (unless they're thoroughly washed)
• Unpasteurised milk
• Pâté made from meat, fish or vegetables
• Blue-veined or mould-ripened cheeses
• Soft-whip ice cream from ice-cream machines
• Precooked poultry and cook-chill meals (unless thoroughly reheated)
• Poor food hygiene and storage practices also increase the risk of someone developing listeriosis

Symptoms

For many healthy adults, the infection doesn't cause any symptoms and so goes unnoticed. In others, it may cause a 'flu-like' illness with headache, fever, sore throat and muscle aches.

Causes and risk factors

Although anyone can be affected by it, Listeriosis causes particular concern in pregnant women. Contracting listeria during pregnancy may result in miscarriage, stillbirth or severe illness in the newborn baby. This is why great emphasis is placed on improving awareness of the risks of listeria infection among women who are pregnant or are trying to conceive.

However, older people and those with weakened immunity may also be more severely affected.

Treatment and recovery

When the infection is mild, usually no treatment is needed. For those more severely affected, treatment in hospital with intravenous antibiotics may be required.