German investigations into a Salmonella outbreak that sickened more than 100 people have once more pointed to Italian tomatoes as the source.
A Salmonella Strathcona outbreak during the 2025-2026 season involved 116 cases in Germany, comprising 100 confirmed and 16 probable infections.
Patients were classified as confirmed cases if they fell ill between June 2025 and March 2026 and whole genome sequencing analysis of the data identified the same outbreak strain as in previous years, according to the Robert Koch Institute (RKI).
Illnesses are part of a long-standing annual outbreak trend. Between 2011 and 2024, more than 600 cases were identified across 17 European countries.
RKI said despite investigation findings which have been available for several years, cases of Salmonella Strathcona are again being identified this season – both in Germany and other European countries -involving isolates that are closely related to the outbreak cluster from previous years. RKI has recorded 39 cases associated with the outbreak since June 2026. Interviews again point to stays in Italy during the exposure period and to consumption of tomatoes.
2025-2026 outbreak
In the last season, cases occurred primarily between August and December 2025 in 13 federal states. The first case was at the end of June, and the epidemic curve showed an outbreak persisting over several months, with the most patients in late October. Cases continued to occur regularly in 2025, but only sporadically at the beginning of 2026.
For 80 of the 116 outbreak cases, information on the country where infection likely occurred was available. Germany was the place of exposure for 48 cases. For 32 cases, exposure was abroad with 27 of these linked to Italy.
The age of ill people ranged from less than 1 to 87, with half of them between 24 and 64 years old. The median age was 39. Women were affected more than men with 66 female and 49 male cases.
Data on hospitalization was available for 91 affected individuals. Of these, 24 were hospitalized because of salmonellosis, and six for other reasons.
Salmonella Strathcona isolates submitted between June 2025 and March 2026 were closely related to isolates from previous outbreaks and the strain detected in 2025 in Austria from Italian organic cherry tomatoes. Experts said this pattern is consistent with a common source.
Of the 116 cases, 30 were interviewed by the RKI via telephone. The majority reported having consumed tomatoes during the exposure period. Of the 17 people whose exposure occurred abroad, 16 had eaten tomatoes.
Five sick people exposed in Germany said that they had purchased tomatoes from the same supermarket chain. Supply chain tracing by authorities revealed that tomatoes from Italy were being sold there during the period in question.
Italian authorities detected Salmonella Strathcona in the irrigation water of a tomato producer in Sicily. An isolate obtained in April 2025 was linked to the outbreak cluster. These findings suggested that the production environment, and irrigation water especially, may have played a role in contamination of tomatoes.
