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bioRxiv · 10.64898/2025.12.08.692485

High pathogenicity avian influenza virus H5N1 (clade 2.3.4.4b) drives mass mortality in Eurasian crane (Grus grus) populations in Germany, 2025

Guenther, A.·Herrmann, C.·Sehl-Ewert, J.·Piro, S.·Ahrens, A. K.·Calvelage, S.·Pohlmann, A.·Beer, M.·Harder, T.
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Abstract

In autumn 2025, an unprecedented mass mortality event was observed among the western migrating subpopulation of Eurasian cranes (Grus grus) in Germany. Systemic infection with highly pathogenic avian influenza virus H5N1, clade 2.3.4.4b, genotype DI.2.1, was identified as the cause of acute death. The gregarious behaviour of cranes at feeding and resting sites likely has contributed to the rapid and massive dissemination of viruses within the crane population.

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Guenther, A., Herrmann, C., Sehl-Ewert, J., Piro, S., Ahrens, A. K., Calvelage, S., Pohlmann, A., Beer, M., Harder, T.. 2025-12-11. High pathogenicity avian influenza virus H5N1 (clade 2.3.4.4b) drives mass mortality in Eurasian crane (Grus grus) populations in Germany, 2025. https://doi.org/10.64898/2025.12.08.692485

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