Multi-country outbreak of Listeria monocytogenes linked to fish products

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.

Advanced molecular typing A way of identifying specific strains of organisms by looking at their genetic material. Often used to characterise bacteria or viruses. techniques identified a variant of Listeria monocytogenes which was detected in the majority of the 2022-2023 cases. The 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 Lithuanian plant, likely reducing the risk of infections. 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 Listeria which could be present in ready-to-eat foods.