This brings up something I'd like some input on. I got a flu shot once...and got sick later on that winter. (I no longer remember the time frames on all this, but it was probably around 2008-2010 or so.)

But that's not what I'm interested in. When I was younger, every single year, which for me was the first three weeks of September, immediately following the first day of school after summer vacation, I would ALWAYS get sick with something resembling "flu." I always chalked it up to being exposed to "germs" from other kids and being away from them for three months. But is there another alternative explanation? Were school custodians cleaning classrooms with some toxic chemical that left residual stuff everywhere in concentrations high enough to make people sick? This was during the 1960s and 70s.

I'd appreciate thoughts on this...I also have been trying to make sense of the "germ" vs. "terrain" theories, but not making much progress.