Nope. Got a flu shot about six weeks ago, felt crappy for a few days after that, then went to my usual happy self...
Same here. My school gives free flu vaccines to their teachers and I take them up on it every year.
One can reduce their chances of getting sick by frequently washing their hands, eating a healthy diet, getting plenty of sleep, drinking plenty of fluids (although I like Blitz's 'alcohol prescription') and laughing a lot.
All help keep the stress level down and the immune system up.
I do admit, I am a reformed hypchondriac
(thanks to anti-depressants). I was constantly worried I was going to get sick and die from the common cold. Funny how I seem to be healthier when I stopped being worried all the time.