Multiple-Clade H5N1 Influenza Split Vaccine Elicits Broad Cross Protection against Lethal Influenza Virus Challenge in Mice by Intranasal Vaccination

The increase in recent outbreaks and unpredictable changes of highly pathogenic avian influenza (HPAI) H5N1 in birds and humans highlights the urgent need to develop a cross-protective H5N1 vaccine. We here report our development of a multiple-clade H5N1 influenza vaccine tested for immunogenicity and efficacy to confer cross-protection in an animal model.