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bioRxiv · 10.1101/2025.10.16.682947

Unexpected Detection of Highly Pathogenic Avian Influenza (HPAI) H5N1 virus in bovine Semen

Lim, A.·Poulsen, K.·Caserta, L. C.·Guan, L.·Opgernorth, E.·Beal, M.·Eisfeld, A. J.·Kawaoka, Y.·Diel, D.
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Abstract

Since March 2024, HPAI H5N1 virus has infected dairy cattle in the U.S., prompting concern about novel transmission routes. During an outbreak in California, HPAI H5N1 RNA was detected in an asymptomatic bulls semen. Although infectious virus was not isolated, questions remain about semen-associated transmission risks and biosecurity practices.

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Lim, A., Poulsen, K., Caserta, L. C., Guan, L., Opgernorth, E., Beal, M., Eisfeld, A. J., Kawaoka, Y., Diel, D.. 2025-10-17. Unexpected Detection of Highly Pathogenic Avian Influenza (HPAI) H5N1 virus in bovine Semen. https://doi.org/10.1101/2025.10.16.682947

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