Public health surveillance of Yersinia species in England, 2017-2024.

Yersinia pseudotuberculosis and Yersinia enterocolitica are globally found zoonotic gastrointestinal bacteria known to cause human infections, transmitted by consumption of contaminated food or environmental contact. Y. enterocolitica is the dominant species in causing yersiniosis, and is under ascertained in England. Diagnostic laboratories across England undertake detection of Yersinia in stool and other sterile sites using UK Standards for Microbiology Investigations. In 2022, there was an exceedance of invasive and gastrointestinal Yersinia notifications across England. Recommendations were made that all Yersinia detected in diagnostic laboratories be cultured and sent to England's national reference laboratory, Gastrointestinal Bacteria Reference Unit, UK Health Security Agency for whole genome sequencing, speciation, genomic profiling, and clustering. Here we describe the epidemiology of all Yersinia spp. reported in England to the UKHSA from the regional laboratories and the reference laboratory leading up to and following the exceedance in 2022. We aim to capture and describe the changes and developments in surveillance of Yersinia spp. between 2017 and 2024.