Recent listeriosis cases linked to a company

Twelve cases of listeriosis have been recorded between September and January, all linked to products made by the company Drôme Ardèche Tradition in Bourg-de-Péage. Two people over 75 years old died, and the median age of the affected patients is 81 years, with eleven of the twelve patients being over 65 years old.

Company action after the outbreak

In response to the outbreak, a prefectural decree was issued to suspend the company's activities. The company has since initiated the withdrawal and recall of all products made at its site to prevent further illness.

Previous listeriosis outbreak in August

This cluster of cases echoes a previous incident in August, when at least 21 cases of listeriosis were recorded, including two deaths, linked to pasteurized milk cheeses from the Chavegrand dairy. The situation led to a legal investigation involving charges of involuntary homicide, injuries, and deception.

Rising listeriosis cases over recent years

Since 2021, the number of listeriosis cases has been increasing continuously, reaching 619 reported cases in 2024. This represents an incidence of 9 cases per million inhabitants, up from 3.1 to 6.2 previously. The increase is most pronounced in older individuals, with an incidence of 87 cases per million among those over 90 years old.

Expert explanation for the rise in cases

Marc Lecuit, an infectious disease specialist at the Pasteur Institute, explained that the rise in cases is not due to more contaminated food or reduced surveillance but is linked to an aging population and the progression of chronic diseases. This trend is also observed in other European countries.

Listeriosis: rare but serious

Listeriosis remains a rare foodborne infection, accounting for less than 0.1% of foodborne infections in France. However, it is the second leading cause of death from food poisoning after salmonella, with several dozen deaths each year. A 2017 report by Santé publique France noted about 65 annual deaths for 400 to 500 cases recorded.

High-risk groups and symptoms

Certain populations are particularly vulnerable to listeriosis, including the elderly, pregnant women, newborns, and immunocompromised individuals. In adults, symptoms may include fever, muscle aches, digestive issues, and in severe cases, septicemia or meningitis. In pregnant women, the infection may be mild or unnoticed but can still endanger the fetus.

Challenges in identifying the source

A unique challenge with listeriosis is its long incubation period, which can last up to eight weeks, making it difficult to identify the contaminated food. Foods that carry a higher risk include fermented sausages, soft-ripened raw milk cheeses, deli meats, smoked fish, sprouted seeds, and ready-to-eat meals. Contaminated products appear identical to healthy ones, making vigilance difficult without official warnings.

Prevention and safety measures

The good news is that cooking eliminates the bacterium, a simple but effective measure to protect vulnerable populations. This method remains one of the best daily protections against listeriosis, especially for those at higher risk.