Listeria/Listeriosis: symptoms, diagnosis and treatment

Listeriosis is an infectious disease transmitted by a bacterium (Listeria monocytogenes), which in most cases is transmitted through food. In most cases of infection, the infected person does not become ill, but the bacteria is dangerous for pregnant women, babies, the elderly and people with reduced resistance. Listeriosis is a disease that is rare in the Netherlands.


  • Fever
  • Chills
  • Pain in the back
  • Headache
  • A sore throat
  • muscle strain

The symptoms are largely similar to flu, making the disease very dangerous. People who become ill due to the listeria bacteria require rapid intervention. Pregnant women must be very careful. The listeria bacteria can cause serious damage to the fetus, causing the child to be born with disabilities. There is also a risk of miscarriage or the birth of a dead child. In addition, sick people run the risk of developing life-threatening meningitis or blood poisoning.

Listeria bacteria

Listeriosis is caused by the listeria bacteria (Listeria monocytogenes). This bacterium is mainly found in food, but listeria can also occur in animals, crops and water. Theoretically, the bacteria can also be transmitted from humans through feces, but this is very rare. A pregnant woman can pass the bacteria on to her baby. The listeria bacteria thrive especially in unpasteurized milk, pâté and pre-packed salads. If food is stored incorrectly, the listeria bacteria have free rein to reproduce quickly. Patients with iron overload disease are also at increased risk of developing listeriosis.


The diagnosis of listeriosis follows extensive examination. This is done by questioning the patient and performing a physical examination. The symptoms of listeriosis appear common with many diseases. That is why it is important to exclude other diseases such as salmonellosis, botulism and E.coli through examinations. Listeriosis is definitively diagnosed by culturing the listeria bacteria. This can be done via blood, cerebral fluid or amniotic fluid. Stool is not suitable for carrying out a listeria test.


In patients without complaints, listeriosis does not need to be treated. If someone is seriously ill, they will be admitted to hospital. This certainly applies to pregnant women. Patients are given antibiotics through an IV. The number of days antibiotics are administered depends on the stage of the disease. If meningitis occurs, antibiotics are administered for three weeks. When an abscess is found in the brain, at least six weeks. For a pregnant woman, a pediatrician and obstetrician are also involved in the treatment.


Avoid risky products

There are ways to minimize the chance of getting listeria. Pregnant women and people with a weakened immune system in particular are advised not to eat a number of risky products. This applies to cheese with raw milk, raw meats such as pâté, carpaccio, filet américain, tartare and roast beef, smoked fish, marinated fish, smoked mussels, unpasteurized milk, ready-made pancakes and soft ice cream.

Preparing food

Raw vegetables must be cleaned thoroughly beforehand. Raw food should be separated from prepared food. It is important that meat and fish are always well done. Leftovers should not be kept for too long. Do not consume food that has expired. Always keep kitchen utensils clean and use clean materials when preparing food. A dishcloth is always full of bacteria. It is better to use a kitchen roll with kitchen paper instead of a dishcloth. Meat should be cooked or roasted at a minimum of 70 degrees. The listeria bacteria will not survive that.