Ailam Lim, Keith Poulsen, Leonardo C. Caserta, Lizheng Guan, Eryn Opgenorth, Maxwell Beal, Amie J. Eisfeld, Yoshihiro Kawaoka, Diego G. Diel
Since March 2024, highly pathogenic avian influenza (HPAI) A(H5N1) virus has infected dairy cattle in the United States, prompting concern about novel transmission routes. During an outbreak in California, HPAI H5N1 RNA was detected in an asymptomatic bull's semen. Although infectious virus was not isolated, semen-associated transmission risks and biosecurity practices remain a concern.