Then what does it have in it that mitigates the flu ?
My Doc said the flu viruses are chopped up into little pieces and not a complete viral DNA strand so you develop antibodies but not the flu. At least that is what I thought he said - he’s a mumbler and I’m almost deaf.
That said 2 weeks after my first ever flu shot I got a really bad flu...
Except for the nasal spray version, flu vaccines use inactivated virus pieces that have surface proteins to which the body’s immune system reacts, producing antibodies. Here is more detail:
https://www.publichealth.org/public-awareness/understanding-vaccines/vaccines-work/