Everybody was already exposed, including you, when he had the diarrhea a few days back. So if it's flu you're in trouble, but I truly hope not!

Vomit & bad diarrhea mean that I expect a parent to be there immediately or sooner, but I never turn a child away due to a virus. Don't feel guilty at all. I have a vaccination policy in my contract and I ask my clients to get the doctor's appointments on Friday afternoons so the children are at home with their parents for 48 hours before coming to daycare. I shouldn't be monitoring for adverse reactions after shots, it's the parents responsibility if their child becomes sick from it.