Italy, the Hardest-Hit Country in the European Salmonella Strathcona Outbreak in Sicilian Cherry Tomatoes

On November 12, 2024, ECDC and EFSA jointly published a Rapid Outbreak Assessment on the cross-border outbreak of Salmonella Strathcona ST2559, which by that date affected 16 countries across the European Union, the European Economic Area and the United Kingdom. Italy was the hardest-hit country, with 123 confirmed cases, concentrated between late September and early October 2024 in the Tuscany and Umbria regions, where more than 300 additional symptomatic cases linked to primary schools and childcare centers were also reported. Epidemiological investigations confirmed that cherry tomatoes grown in Sicily were the source of infection in both the 2024 Italian outbreak and a prior outbreak recorded in Austria in 2023. A subsequent European audit of Sicilian producers identified staff shortages on farms and inconsistent controls over the quality of irrigation water used.

That the same origin — cherry tomatoes from a specific Sicilian growing region — should have caused outbreaks in different countries and different years points to a persistent problem in source control rather than an isolated incident: ECDC's cumulative assessment as of September 30, 2025 already tallied 437 confirmed cases across 17 European countries, 205 more than reported in the first November 2024 assessment. Contaminated irrigation water is a transmission route that is particularly hard to control in raw-eaten vegetables such as cherry tomatoes, because the pathogen can adhere to the fruit's surface or even be absorbed through microfissures in the skin, without any post-harvest wash managing to remove it completely.

For TAAG, that Italy should concentrate the highest number of cases of an outbreak whose root cause — irrigation water without consistent control — was identified as early as the first 2024 audit, and that the outbreak keeps adding cases year after year, confirms that microbiological monitoring of irrigation water at the source is an investment the fresh-produce sector can no longer keep postponing: traceability of a contaminated cherry tomato becomes practically impossible to reconstruct once the product reaches a supermarket shelf in another country.