Immunogenicity and efficacy of a rabies-based vaccine against highly pathogenic influenza H5N1 virus

The recent spillover of highly pathogenic influenza A/H5N1 (HPAI-H5N1) viruses to cattle, other mammals, and humans poses a major risk to animal and human health. Virus adaptation to new species highlights the need for effective vaccines for animals and humans. We recently developed a rabies virus-based H5 vaccine encoding the HPAI-H5 antigen and presenting it on the surface of the rabies virus particle. To test the immunogenicity and efficacy of the vaccine in eliciting systemic and mucosal immune response, we vaccinated mice intramuscularly or intranasally with either live or inactivated and adjuvanted vaccine. The vaccine elicited neutralizing antibodies against RABV and H5N1 Influenza virus and protected mice from a lethal challenge with PR8 recombinants reassorted with the HA of clade 1 (Viet Nam 1203) or clade 2.3.4.4b HPAI-H5N1 viruses, highlighting its potential use in mitigating the risk of HPAI-H5N1 pandemic.