Immunogenicity and safety of a rabies-based highly pathogenic influenza A virus H5 vaccine in cattle

The circulation of highly pathogenic H5 influenza A viruses in cattle, other mammals, and wildlife threatens animal and human health. To address this, we vaccinated heifer-calves with a deactivated rabies-virus-based H5 vaccine, which was well-tolerated and elicited neutralizing antibodies against both clade-1 and clade-2.3.4.4b H5N1 viruses, comparable to naturally H5-infected and convalescing cows. The immune responses to the vaccine platform were durable for at least 200 days and unaffected by preexisting RABV immunity.