But kids who are 6 and up often do feel much more ill. So, in the pre-vaccine days I can understand parents wanting their kids to be exposed to CP before school-age.
You're telling me. I missed the first wave when I was about five, and ended up catching it when I was ten. My friend's little brother infected me, I think - although she came down with it two days after I did, bizarrely.
I was sick as a dog. They were everywhere, and I couldn't even cross the room without sitting down for a rest. That said, another friend's mother came down with them at about the same time and she was
seriously ill. So I suppose catching it at ten is better than later. (My ex was fifteen when he caught it, and ended up growing a beard around the pox.)