National Outbreak of Yersinia Under Investigation in Norway

Norway

The Norwegian Institute of Public Health is investigating a national outbreak of Yersinia enterocolitica O3, a gastrointestinal infection. Nine people have been confirmed infected, with six more suspected cases. The affected individuals are spread across several regions, including Trøndelag, Vestfold, Telemark, Østfold, Innlandet, Rogaland, and Vestland in Norway.

The outbreak investigation is being conducted in collaboration with the Norwegian Food Safety Authority, the Norwegian Veterinary Institute, and municipal doctors. The primary goals are to determine the extent of the outbreak, identify the source of infection, and prevent further spread. The infected individuals, aged between 10 and 75, were sampled between May 26 and June 15, with a median age of 29. Eleven of the confirmed cases are women. Genetic analysis of the bacterial samples indicates a common source of infection.

The outbreak was discovered through routine health surveillance and laboratory testing. The reference laboratory at the Norwegian Institute of Public Health is analyzing bacterial samples to confirm their connection to the outbreak. Interviews with affected individuals are ongoing to trace their food and water consumption and other potential exposures.

Source: www.fhi.no/nyheter/2026/nasjonalt-utbrudd-av-yersinia/