wnjj wrote:
From the definition: "A product that stimulates a person’s immune system to produce immunity to a specific disease, protecting the person from that disease."
The issue with the annual flu vaccine is that it doesn't always target the proper "specific disease" that ends up in circulation, hence people get sick from the one that does. The "flu" is not specific but rather a family of viruses.
So technically the flu shot is a vaccine or a cocktail of more than one vaccine. Practically speaking it may or may not be effective during "flu season" due to the varied flavors.
You are debating with someone that thinks the flu is one virus.