Sick kid at camp

So I am helping out at a horse camp for a littler children (ages 6-9 ish) and what is the kids that was there had told the camp director that he had thrown up the night before coming. Now, I don’t know if this is 100% true or not coming from a little kid, but if it was don’t you think the parents should’ve at least told us something? I know that there is a role in most schools that says students have to wait at least 24 hours after their last symptom before coming back to school. Honestly, I thought that was common sense but I guess not. Now, I have a stomachache, stuffy nose, and my voice seems a little off. I really hope that I don’t get sick because of a parents lack of common knowledge.