Salmonella Typhimurium Outbreak in Denmark

Denmark

Update June 30th, 2026:
Danish health authorities have identified 26 confirmed cases of monophasic Salmonella Typhimurium ST34, an increase from the previously reported 25 cases.

The outbreak has affected people between 8 and 81 years of age, with cases reported across five regions of Denmark. Investigators continue to examine the outbreak through whole-genome sequencing and patient interviews, but the source of the infection has not yet been identified.

The outbreak remains under investigation by the Statens Serum Institut, the Danish Food, Agriculture and Fisheries Agency, and the National Food Institute.

Source: Statens Serum Institut (SSI)


June 16th, 2026:
The Statens Serum Institut has reported an outbreak of monophasic Salmonella Typhimurium sequence type 34 in Denmark, with 25 cases identified since May 2026. The affected individuals, ranging from 8 to 81 years old, are spread across various regions, including the capital, North Jutland, Southern Denmark, Zealand, and Central Jutland.

The outbreak is under investigation by the Central Outbreak Group, comprising the Statens Serum Institut, the Danish Food, Agriculture and Fisheries Agency, and the National Food Institute of Denmark. Efforts are focused on whole-genome sequencing of bacterial isolates and conducting patient interviews to trace the source of the infection. As of now, the specific source of the outbreak remains unidentified.

The problem was discovered through routine surveillance by the Statens Serum Institut, which registered the cases and identified the genetic similarity among the bacterial strains. This prompted further investigation to determine the outbreak's scope and potential source. The authorities continue to monitor the situation closely to prevent further spread and identify the contamination source.

Source: www.ssi.dk/sygdomme-beredskab-og-forskning/sygdomsudbrud/2026_salmonella_typhimurium_st34