Mutations in the Hemagglutinin Stalk Domain Do Not Permit Escape from a Protective, Stalk-Based Vaccine-Induced Immune Response in the Mouse Model

Broadly protective or universal influenza virus vaccines target viral epitopes that appear to be conserved. However, it is unclear whether the virus will be able to escape once immunological pressure is applied to these epitopes through vaccination of large proportions of the population. Studies that investigate the fitness and antigenic characteristics of viruses that escape immunological pressure on these conserved epitopes are therefore urgently needed.