How Does the Hemagglutinin Stalk Relate to Antigenic Drift and Shift?
Influenza viruses undergo two types of genetic changes: antigenic drift and antigenic shift. Antigenic drift involves small changes in the virus's genetic makeup, particularly in the hemagglutinin head, leading to new strains that can evade the immune system. Antigenic shift, on the other hand, involves a significant reassortment of viral genes, potentially leading to new pandemics. Because the stalk region is more conserved, targeting it could provide cross-protection against various strains, including those arising from antigenic drift and shift.
