Infection of ratites with clade 2.3.4.4b HPAIV H5N1: Potential implications for zoonotic risk

Coombes, H. A.; Terrey, J.; Schlachter, A.-L.; McCarter, P.; Regina, I.; Hepple, R.; McGinn, N.; Seekings, J.; Cooper, J.; Clifton, B.; Mollett, B. C.; Falchieri, M.; Nunez, A.; Reid, S. M.; James, J.; Banyard, A. C.

doi:10.1101/2025.09.08.674895

bioRxiv · 10.1101/2025.09.08.674895

Infection of ratites with clade 2.3.4.4b HPAIV H5N1: Potential implications for zoonotic risk

Coombes, H. A.·Terrey, J.·Schlachter, A.-L.·McCarter, P.·Regina, I.·Hepple, R.·McGinn, N.·Seekings, J.·Cooper, J.·Clifton, B.·Mollett, B. C.·Falchieri, M.·Nunez, A.·Reid, S. M.·James, J.·Banyard, A. C.

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Abstract

We detected H5N1 high pathogenicity avian influenza in captive Greater Rhea (Rhea americana). Viral genetic analysis revealed the mammalian associated PB2-E627K mutation, indicating selection of mammalian-relevant mutations in ratites. Pathologic investigation of available tissues demonstrated severe multifocal necrotising inflammation, and a strong vasculotropism.

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Coombes, H. A., Terrey, J., Schlachter, A.-L., McCarter, P., Regina, I., Hepple, R., McGinn, N., Seekings, J., Cooper, J., Clifton, B., Mollett, B. C., Falchieri, M., Nunez, A., Reid, S. M., James, J., Banyard, A. C.. 2025-09-10. Infection of ratites with clade 2.3.4.4b HPAIV H5N1: Potential implications for zoonotic risk. https://doi.org/10.1101/2025.09.08.674895

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