Licensed H5N1 vaccines generate cross-neutralizing antibodies against highly pathogenic H5N1 clade 2.3.4.4b influenza virus.

The emergence of highly pathogenic avian influenza (HPAI) H5N1 clade 2.3.4.

Intranasal immunization with influenza antigens conjugated with cholera toxin subunit B stimulates broad spectrum immunity against influenza viruses.

Frequent mutation of influenza viruses keep vaccinated and non-vaccinated populations vulnerable to new infections, causing serious burdens to public health and the economy. Vaccination with universal influenza vaccines would be the best way to effectively protect people from infection caused by mismatched or unforeseen influenza viruses. Presently, there is no FDA approved universal influenza vaccine.