I agree 100%, kiwi33, although I'm not sure that's clear from what I wrote!

What I was trying to say was that the hypothesis that "PD progression speeds up while you have the flu" is currently only supported by anecdotal evidence and animal studies. For this reason I think it should currently play no role in the decision on whether or not to have an annual flu shot.

As you pointed out, factors such as an individual's general health, living/working environment, etc. should be the guide.

I should have added something along these lines to help avoid misunderstandings.