The difference is the flu virus keeps mutating while with phages you have a large collection and choose the ones that work on the infection the patient has. Th

The difference is the flu virus keeps mutating while with phages you have a large collection and choose the ones that work on the infection the patient has. The big problem with the flu vaccine is the lead times are so long (6 months) that the vaccine producers need to guess what strains will be circulating 6 months ahead. Since they lack a crystal ball they often get it wrong. The only real advance with the cellular vaccines is for people allergic to egg. I am not that hopeful that a universal flu vaccine will get funded.