A multi-country foodborne illness outbreak of Listeria monocytogenes, in which smoked salmon is the suspected cause, has resulted in two deaths, reports the European Food Safety Authority (EFSA) and the European Center for Disease Prevention and Control (ECDC).

Between 2022 and 2023, the outbreak has affected Austria, Belgium, Italy, Germany, and the Netherlands, with reports of 17 cases and two deaths. Infections have occurred mainly in the elderly. Historical human cases related to the outbreak have been detected since 2011. Ready-to-eat (RTE) fish products, mainly smoked salmon, are the likely vehicle of infection.

Advanced molecular typing techniques identified a variant of L. monocytogenes, which was detected in the majority of the 2022–2023 cases. Analysis of the data suggests a connection to two establishments in Lithuania during the same period. These establishments were found to have introduced contaminated fish products into the retail markets of Germany and Italy. Production has been stopped in a suspected Lithuanian plant. Data regarding the distribution of contaminated products in Austria, Belgium, and the Netherlands is currently not available.

EFSA and ECDC experts say that further investigations are needed to identify the origin of the contamination. This will allow national authorities to implement targeted control measures and mitigation actions. Experts also recommend following good manufacturing practices, hygiene rules, and effective temperature control throughout the entire food production, distribution, and storage chain, including in households. Consumers are advised to maintain low refrigerator temperatures to inhibit the potential proliferation of bacteria such as L. monocytogenes that could be present in ready-to-eat foods.