Influenza Immunity: New Insights from Old Studies

摘要

All viruses mutate, but influenza remains highly unusual among infectious diseases in the rapid evolutionary rate of its causative viruses. The defensive response of the human immune system to repeated viral attacks is both the driving selective force in the evolution of new viral variants and, indirectly, the determinant of the subsequent compromised ability of the immune system to protect against the new variants. As a consequence, new vaccines are needed almost every year if an optimal match of vaccine and new (immunose-lected) challenge virus is to be achieved.