The effectiveness of the vaccine is in preventing infection, not in making the symptoms less severe.
I do not quite agree with you. In my opinion, preventing infection would be avoiding contact with the virus, this is not what the vaccine does. For the anti-bodies from the vaccine to become active, the virus has to be contacted and then is being fought by the anti-bodies. The advantage of the vaccine would be that the anti-bodies are already available and do not have to be build by the immune system after contacting the virus. At least that is how I remember it from immunology.
Thus to have the proper antibodies you have to know exactly what virus you are fighting and that is not always very clear with the flu-vaccines.
Not exactly. Antibodies are 'dumb' agents, they don't scan the virus for DNA, but identify some of the protein molecules on its surface. The name "H1N1" for a flu strain refers to versions of two of these surface molecules, hemagglutinin (the H) and neuraminidase (the N). So vaccination doesn't have to concentrate on the entire virus genome to trigger the production of the right antibodies. In the case of flu, with its several parallel strains that have different activity in different seasons, that means a bit of routine.
From what I read, a significant part (if not the majority) of ineffective vaccinations is infection with strains of flu that make up the minority of infections in a season and weren't considered in that season's mix. *Lunatic*, n. One whose delusions are out of fashion.
