According to the European Center for Disease Control (ECDC), whole genome sequencing (WGS) has revealed close genetic relatedness among the outbreak strain and Salmonella isolates that have been detected since 2011, indicating a recurring, seasonal public health concern. New outbreaks are likely to occur in future seasons until the root cause of the contamination has been identified and control measures are implemented.

Specifically, 289 cases of S. Strathcona ST2559 have been confirmed thus far, with sequencing still pending for 23 additional cases.

The greatest number of cases were reported in Italy (78) followed by Germany (68) and Austria (59). In the North American continent, eight cases were reported in the U.S. and five in Canada. Of travel related cases, Italy was the most commonly reported destination.

Most cases have occurred in the summer months (between June and October) in all years. The recurrence of cases in 2025, including those without travel history, suggests ongoing transmission and distribution of contaminated produce beyond Italy.

Interestingly, three isolates from Italy tested positive for lactose fermentation, an unusual trait for Salmonella, which could have an impact on identifying Salmonella using traditional selective media. Therefore, it is possible that the true number of cases are underestimated.

ECDC, in collaboration with the European Food- and Waterborne Diseases and Zoonoses Network (FWD-Net) and the European Food Safety Authority (EFSA), are continuing to monitor the outbreak and coordinate response efforts. Further investigations are planned in some affected countries, including WGS analysis.