My big pet peeve is restaurant workers who work sick. I think it should absolutely be disallowed!
I stayed home from church a couple of weeks ago with a cold because I didn't want to pass it on. On the other hand, we did all go to a family Christmas party last year at the tail end of the flu
I don't think it's good to avoid all illness. Our immune systems need some practice but it's easy enough to catch stuff without people going to church sick. BTW, does anyone else NOT want to shake hands at church? I think it is gross and I don't know how to politely get around it.