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Intraductal #infection with #H5N1 clade 2.3.4.4b #influenza virus

LETTER

In March 2024, highly pathogenic avian influenza (HPAI) H5N1 of the clade 2.3.4.4b was detected in dairy cows in Texas and has since been detected in several other U.S. states (1). Virus has been detected within cow’s milk, indicating that the mammary epithelium may support viral replication (2). Virus has also been detected on milking machines, leading to a hypothesis that influenza is spreading through fomites from udder to udder instead of the intranasal route (3, 4). There have been studies using cows to better understand mammary infections; however, the cow model is costly and limited (1, 5). We sought to establish a model for intramammary infections of H5N1 and H1N1 influenza virus in mice.

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Source: Journal of Virology, https://journals.asm.org/doi/full/10.1128/jvi.01927-24?af=R

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