Cross-reactive responses induced by the consensus NA, however, were not examined.29,30 In the present study, we describe a consensus-based approach that broadens the antibody response directed towards influenza NA, leading to coverage of N1 strains from 1934 until recent times, and highlighting the potential of NA designs as vaccine candidates capable of providing broad intrasubtypic (with respect to NA) protection against influenza. The gene discussed is XK; the disease is influenza.