The story is tragic and serves as a global health reminder. In the United States, the Department of Health has confirmed the death of an infant who contracted the bacteria Listeria monocytogenes while he was still in his mother’s womb. The latter, however, only experienced mild symptoms after consuming unpasteurized milk.
This discrepancy between the benignity of the maternal infection and the severity of the fetal damage is the most formidable characteristic of this disease, which remains the third cause of dietary mortality.
An insidious infection that is difficult to diagnose
Listeriosis is not like classic food poisoning that occurs a few hours after a meal. Here, time is a confounding factor. According to Dr. Gérald Kierzek, “listeriosis is a dangerous infection that can go unnoticed in its mild forms, but become serious in some patients“In fact, after ingesting a contaminated product, the first signs can appear within two days or only appear eight weeks later.
In its most common form in healthy adults, it resembles a temporary flu-like illness with a moderate fever of around 38°C, muscle pain and sometimes some digestive problems such as nausea or diarrhea. However, in fragile subjects, the bacteria can migrate to the nervous system, causing intense migraines, neck stiffness or mental confusion, signs of possible meningitis.
The placental barrier: an impotent protection
The specific danger for the pregnant woman lies in the exceptional capacity of the Listeria to cross the body’s natural barriers. Once the bacteria has entered the digestive system, it enters the bloodstream and manages to cross the placenta, directly reaching the fetus which does not yet have an immune system capable of fighting.
“Flu symptoms in pregnant women should always be taken seriously, as listeriosis can lead to miscarriage or infect the fetus.” insists Dr. Kierzek. If the disease is not treated urgently with appropriate antibiotic therapy, the consequences are dramatic: they range from premature delivery to neonatal sepsis, including serious pulmonary or neurological infections from birth, or even death in utero.
Support: the importance of a rapid consultation
It is crucial not to let a persistent fever linger during pregnancy, even if it seems not serious. The medical diagnosis is generally based on a blood test to detect the presence of the bacteria. In cases where neurological symptoms are observed, a lumbar puncture may be necessary to rule out any risk of meningitis.
As our expert points out, hospitalization is not systematic but remains an option for severe forms. “Treatment will be based on antibiotics, with possible hospitalization for severe forms. says Dr. Kierzek. The objective is then to stop bacterial multiplication as quickly as possible to limit collateral damage to the baby’s development.
Prevention, pillar of food security
Since the bacteria is present in the environment and can survive despite the cold of the refrigerator, daily vigilance remains the only effective defense. Raw milk and unpasteurized products are the first vectors singled out by health authorities. For example, the American CDC points out that pasteurized milk offers the same nutritional benefits without any of the associated risks.
Finally, “prevention remains the best weapon” recalls Dr. Gérald Kierzek. To protect the most vulnerable, it is important to be uncompromising when it comes to kitchen hygiene and the choice of products. “Avoid foods at risk for fragile people (raw milk cheeses, cold meats, smoked fish, raw sprouted seeds), cook animal products and leftovers well, and clean your fridge regularly, because Listeria is resistant to cold.” he concludes.