Could one vaccine protect against everything?

There's a vaccine being developed now that would protect you against every strain of the flu— even ones that don't exist yet. But influenza is constantly mutating, so is a universal vaccine even possible? And how do you design a vaccine that will be effective against future strains? Explore how scientists are developing new ways to help our immune systems fight viruses. [Directed by Igor Coric, Artrake Studio, narrated by George Zaidan, music by Nikola Radivojevic].