Listeriosis and pregnancy: symptoms, how to avoid it?

[Mise à jour du 25 janvier 2023 à 10h35] French health authorities recently identified nationwide 5 serious cases of listeriosis including 4 affecting pregnant women who gave birth prematurely. All of them had consumed during their pregnancy plant-based alternatives to cheesebased on almond milk and cashew nuts, manufactured by the brand Jay & Joy, which claims to be 100% vegan, organic and made in France. In a press release, dated January 19, 2023, the Ministry of Health and Public Health France specify that the victims were infected with the same layer of Listeria. They reported their symptoms between April and December 2022. After investigations by the competent authorities, “a prefectural decreeaimed at suspending the marketing of all products stored and manufactured in the factory, has been taken on January 16, 2023″, the statement said. the details of the recalled products can be viewed on the website rappel.conso.gouv.fr. The authorities also recommend for people and pregnant women, who have consumed these products, if they have fever with or without headaches and digestive disorders consult their doctor as soon as possible informing him of what they ate.

Listeriosis and contamination during pregnancy

The listeriosis is a serious infection caused by bacteria Listeria monocytogenes. This bacterium resists cold well and once present in food, it continues to multiply even if it is kept in the fridge. Contamination is almost always foodborne. Most often, the food contaminated by the bacteria is digested and the bacteria neutralized by the immune system, without consequence.

What are the symptoms of listeriosis in pregnant women?

Listeriosis is a disease difficult to diagnose based on symptoms alone. Indeed, the pregnant woman may present only an unexplained cough and fever. flu symptoms may also be present or abdominal pain suggesting gastroenteritis. But in 30% of cases, listeriosis causes no symptoms and is only detected by the consequences it has on the foetus.

How do you know if you are affected by listeriosis during pregnancy?

Listeriosis can be detected in pregnant women using microbiological analyzes, prescribed by a doctor and carried out in the laboratory. Indeed, in this case, the blood test is rarely conclusive to confirm the presence or absence of the bacteria in the body of the pregnant woman. The best technique for detecting listeriosis is to take a sample from a normally sterile site (blood, cervix and vagina, sometimes urine or others) and isolate the bacteria after culturing. However, not all of these sites are necessarily affected by the bacteria and therefore will not necessarily be positive for detection tests.

What are the consequences of listeriosis on the fetus?

This disease mainly affects the elderly or those weakened by diabetes, alcoholism or cancer, etc. However, the pregnant woman being immune weakened, she is 12 times more likely to develop the disease after consuming infected food, compared to a woman who is not pregnant. Severe forms are rare, but can cause miscarriage or premature delivery. Unlike toxoplasmosis, listeriosis has been a notifiable disease since 1998, so the number of cases in France is known precisely and, in the event of a problem, batches of meat can be withdrawn from sale, for example. However, there is no mandatory screening protocol for pregnant women, listeriosis being much rarer. In total, listeriosis represents only 2% of infections in pregnant women.

• Foods to avoid: three categories of food should be avoided during pregnancy to limit the risk of contamination by Listeria. Some cheeses, meats and fish. Indeed, cheeses and dairy products must be pasteurized, well-cooked meats and fish must not be eaten raw.
• Carefully reheat leftover foods and cooked meals (respecting the instructions on the packaging)
• Respect the expiry dates (DLC) appearing on food products
• Wash one’s hands. In addition, hands are the first carriers of germs in food. It is therefore essential to wash your hands regularly, especially after going to the bathroom and before and after preparing a meal and eating.
• The fridge must also be the subject of all attention: its temperature must be set at 5 degrees and the purchased food must be quickly installed in it. Also remember to clean it several times a month.

In what food can listeriosis be found?

Cheeses

Avoid consuming the raw milk preparations. Check that the cheeses have been pasteurized before consuming them. Prefer pressed and cooked cheeses (Emmental, Comté) or spreadable cheeses. The milk needed to prepare them has been heated to a high temperature which destroys the Listeria bacteria. You should also avoid eating cheese rinds, which are full of bacteria of all kinds.

Deli

Rillettes, pâtés, foie gras, jelly products should be avoided during pregnancy to prevent the risk of listeriosis. Indeed, the meat has been processed and bacteria may have contaminated the meat. If you choose ham, take it pre-packaged because it will not have been on the same deli counter as other raw products, which may be contaminated. The best is to consume meat well cooked through and avoid eating it raw (no tartar, etc.).

Fish and seafood

Similarly, there is no question of consuming Piscesof the raw seashells or even surimi or some rillettes of the sea. These products can be dangerous for pregnant women. Do not mix raw and cooked products, keep them away and only eat leftover food and cooked dishes after having heated them sufficiently (at least 65°C for several minutes to kill the parasite). You should also clean your refrigerator regularly, throwing out expired food and disinfecting it with bleach.

What is the treatment for listeriosis during pregnancy?

The bacterium responsible for listeriosis is resistant to cephalosporins, antibiotics commonly used to fight bacterial infections. On the other hand, other antibiotics are very effective such as amoxicillin, aminoglycosides, trimethoprim-sulfamethoxazole (contraindicated during pregnancy), macrolides or even vancomycin. In all cases, if listeriosis is suspected in pregnant women, antibiotic treatment is implemented before the results of the bacteriological examinations are obtained. It is amoxicillin which is given in first intention, for 10 days. When listeriosis is proven, the treatment is increased and can be modified if necessary. The treatment is all the more effective if it is prescribed quickly after the onset of the infection. Any unexplained fever in pregnant women must therefore be treated with great caution.