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#Transmission of #bovine #H5N1 virus in a #hamster #model

LETTER

Transmission among mammals of bovine highly pathogenic avian influenza (HPAI) H5N1 viruses, which have caused outbreaks in US dairy cattle (1–3), has been demonstrated in ferrets by our group (4, 5) and the US Centers for Disease Control and Prevention (CDC) (6). These studies showed that these viruses can be transmitted among ferrets via respiratory droplets, albeit with lower efficiency than seasonal human influenza viruses. In contrast, bovine HPAI H5N1 viruses spread easily among ferrets through direct contact (3 of 3 [100%] ferrets) (6). Although ferrets are frequently used for influenza virus transmission (7–9) and vaccine efficacy (10, 11) studies, they demand considerable housing space and personnel and can be difficult to handle. Here, we investigated the transmissibility of the bovine HPAI H5N1 virus A/Texas/37/2024 (TX/37), which was 100% lethal in ferrets inoculated with as little as 10 plaque-forming units (PFUs) (5) by using a hamster model

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Bovine HPAI H5 virus was thus found to be highly pathogenic and highly transmissible by direct contact in hamsters, although we did not detect respiratory droplet transmission. Therefore, hamsters have potential as a small animal model for analyzing the protective effect of vaccines or antiviral drugs against bovine HPAI H5 virus infection.

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Source: Journal of Virology, https://journals.asm.org/doi/10.1128/jvi.00147-25

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