Cross-border outbreak of bioserotype 2/O:9 infections associated with consumption of French unpasteurised soft goat's milk cheese, 2024.

In March 2024, the French genomic surveillance of enteric yersiniosis identified a cluster of lineage 2/3-9b isolates, corresponding to bioserotype 2/O:9. An outbreak investigation was conducted to identify the source and implement control measures. A total of 175 confirmed cases were identified in France with sampling dates between 27 January and 23 August. Case interviews and trace-back investigations identified unpasteurised soft goat's milk cheese from one manufacturer in France as the probable source of the outbreak. belonging to the same cluster as the case isolates was isolated from 23 samples from the manufacturer and a goat farm supplying milk to the dairy. Cheeses from the manufacturer were recalled in France. A Rapid Alert System for Food and Feed (RASFF) notification was issued, allowing the identification of cheese distribution from the manufacturer to 29 countries. An Epipulse alert led to the identification of seven additional cases in Belgium, Luxembourg and Norway, illustrating the value of international warning systems. This outbreak demonstrates risks with consumption of unpasteurised cheese and emphasises the need of rigorous good hygiene practices on dairy farms and dairies, especially when milk is processed without pasteurisation.