The common cold that you get every 12 to 18 month is a different thing than influenza. A lot of people die of it but the actual incidence is not that high that you get it every year (every 10 years would be quite often actually).

I wasn't talking about the common cold.

If you have kids in school, you're going to get the flu every year or two.

I knew someone who felt exactly the same way, so don't despair :-)

I'm not quite so extreme, but I do avoid flu shots about one out of every three years for the same reason. In any case, I don't get the flu very often.

What? A vaccine is nothing if an outside stressor on the immune system! It is designed to provoke the exact immune system response the real virus would, so it can react more quickly to future infections.

Unless you mean that the upper respiratory tract inflammation itself is what would cause the beneficial effect?

Yes, that's the common refrain - that the vaccine itself serves as that same stressor - and of course that is true, on the date that you take the vaccine.

But from then on, while you certainly maintain information from the vaccine in your immune system, you aren't ramping up the actual mechanisms of your immune system like you do when you actually experience influenza.

Think of the temperature raise, the white blood cell production, possible gastro-intestinal reactions - these are all bodily systems being ramped up to a level of performance they don't typically see.

My thought is that if I "successfully" avoid the flu for, say, the next 40 years, those bodily systems will not be as robust - even if I maintain the informational content of the vaccine itself.

Please, please, do not confuse this or lump this in with kooky anti-science, vaccine opponents. I'm just thinking out loud about how stressors on body systems work - which is what my parent was discussing.

This would be a great theory, if influensa didn't kill ~50,000 Americans every year. Mostly the elderly and the immuno-compromised.

If it weren't for vaccinations, and the associated herd immunity, many more people would be dying to it.