Supposedly there are only a limited number of cold viruses out there (like 130 or so). And after you've had one, you won't react to it the same way the next time your immune system encounters it because you've built up antibodies to that particular virus's protien coat.
So get out there and hug those kiddies! Kiss their sweet little hands! Love them like they're your own, for are they not all OUR children with precious little souls? Fear not, for ye don't walk in the shadow of the valley of Death, ye only have the real world to cope with and a limited number of colds for your lifetime. (bacteria in hospitals, though, that's another icky story entirely
)
"If Americans want to live the American Dream, they should go to Denmark." - Richard Wilkinson