A Salmonella outbreak is being investigated in Sweden that may be linked to imported eggs.
Folkhälsomyndigheten (the Swedish Public Health Agency) said that different types of outbreaks appear to be involved, and that epidemiological evidence that eggs are the cause varies by suspected strain.
Since the beginning of the year, there have been several reports of people infected with Salmonella Enteritidis, with epidemiological research pointing to the consumption of eggs. On some occasions, officials suspect they were imported from Ukraine.
The number of people sickened by each of the suspected outbreak strains ranges between two and 22. The first patients were infected in late 2023 to early 2024, but most cases have an onset of illness from late July to late September. Patients come from all age groups and there is no unusual gender distribution.
An investigation is underway involving regional infection control, municipalities, the Swedish Food Agency (Livsmedelsverket) and the Swedish Public Health Agency.
Negative product tests
Eggs have been sold to private individuals in stores that do not belong to the larger chains, but also to restaurants.
Several patients have consumed soft-boiled or unheated eggs in products such as mayonnaise, béarnaise sauce and pasta carbonara. Eggs from shops and restaurants have been analyzed several times, but Salmonella was not found. This means that there is no microbiological evidence of eggs or products made with them.
In 2023, an outbreak traced back to eggs produced at CA Cedergren, a large Swedish laying hen facility, sickened 82 people. A closely related strain of Salmonella Enteritidis caused a major outbreak in Belgium in 2022, with hundreds of sick people, also linked to a laying hen site in that country.
Raw eggs or foods made with raw eggs from countries other than Sweden, Norway, Finland and Denmark should not be consumed. Properly heating the whole egg or food containing eggs can avoid the risk of infection when consuming such eggs.
Meanwhile, an outbreak of Salmonella Typhimurium appears to be over without the source being found.
Officials believe the source of the infection was likely a food product with a limited shelf life that is no longer on the market.
In August and September, 35 people from 11 different regions became ill. The patients were between 1 and 89 years old, with a mean age of 45 years, and the majority were women, while 11 were men.
Information on possible sources of infection was collected through interviews, questionnaires and purchase receipts from cases, but this did not help identify which foods had caused illness.
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