XK and influenza: In previous studies, bivalent H1 and H3 COBRA recombinant HA vaccines, B COBRA HA vaccines, H5 COBRA virus-like particle vaccines, or N1 COBRA NA vaccines elicited antibodies with HAI and NAI activity against panels of historical and contemporary influenza A and B viruses in mice, ferrets, and non-human primates, following intramuscular injection which translated to the protection of animals against viral challenge with H1N1, H3N2, H5N1, B-Victoria, and B-Yamagata influenza lineages3,19–23.