A Salmonella outbreak in France was likely caused by contaminated eggs from Poland.
Sixteen people fell sick in the Salmonella Enteritidis outbreak, including nine males and seven females. Four people were admitted to hospitals. Patients ranged in age from 1 to 55 years old and mainly had fever and diarrhea, according to Santé publique France.
In response to questions from Food Safety News, the Direction Générale de l'Alimentation (DGAL) said the initial link was established through a survey of patients, which revealed a connection between the onset of symptoms and the consumption of products containing raw eggs. The origin of these eggs was then determined using the code printed on the shells.
The implicated white eggs were sold in supermarkets. They had already been consumed by the time the link between eating eggs and the onset of symptoms was identified, so there was no recall.
DGAL said it had contacted Polish authorities to ensure that all measures are taken to guarantee consumer safety.
Past outbreak
In a previous outbreak, the Île-de-France regional unit of Santé publique France was notified of a cluster comprising 50 cases of Salmonella Enteritidis. The outbreak was the largest ever reported in the Île-de-France region in terms of case numbers, duration and severity.
A total of 103 Salmonella Enteritidis infections were identified by the National Reference Center (CNR). Strains were isolated between August 2024 and January 2025. The median age of cases was 23, and 95 lived in the Île-de-France region. In total, 43 patients were interviewed. Twenty-five people were hospitalized and four required intensive care. All patients recovered.
Five patients were associated with outbreaks linked to three different restaurants and had consumed egg-based products. Among the other 38 cases interviewed, four had also eaten egg-based products at these restaurants, and 29 reported purchasing unbranded eggs in identical packaging from various locations.
A Salmonella strain isolated from mayonnaise sampled at one of the restaurants was identified by the National Reference Laboratory (NRL) for Salmonella as belonging to this genomic cluster. Eggs were the suspected source of the outbreak, although the exact origin was not identified.
Salmonella detection
Meanwhile, scientists have evaluated the impact of the time between sample preparation and incubation on the detection of Salmonella in fecal samples contaminated with various strains.
Current standards for Salmonella detection require an initial pre-enrichment phase of 18 hours at 37 degrees C (98.6 degrees F).
Several times, ranging from 45 minutes to six hours at a room temperature of 21 degrees C (69.8 degrees F) and 4 degrees C (39.2 degrees F), were tested prior to incubation. Results show that a storage time of six hours at 69.8 degrees F between sample preparation and incubation can reduce Salmonella detection by up to 50 percent, particularly at low levels of contamination. This effect can be reduced by sample storage at 39.2 degrees F.
Results, published in the DGAL and ANSES epidemiological bulletin, highlight the importance of minimizing delays before pre-enrichment to ensure accurate detection, said researchers.
Testing involved the Salmonella types Enteritidis, Typhimurium, Virchow, Infantis and Hadar at four different concentrations in buffered peptone water. Detection of Salmonella was higher at holding times of 45 and 90 minutes as well as four hours compared to those with a waiting time of six hours at room temperature.
