XK and infection: The accumulation of point mutations in the antigenic sites of HA enables viruses to evade host immune responses induced by prior infections or vaccinations, resulting in the emergence of new antigenic variants with epidemic potential.3, 4 Anti‐influenza drugs that inhibit the enzymatic activity of NA are available for the treatment and prophylaxis of influenza; however, mutations in the NA active site reduce its susceptibility to NA inhibitor drugs, leading to the emergence of drug‐resistant variants.5, 6