Sick kid at camp

So I am helping out at a little kid horse camp. The kids there are about eight years old give or take a few years. One of the kids that was there, had told the camp director that he had thrown up the night before coming to camp. Now, I don’t know if this is 100% true are not, coming from a little boy, But even if he had thrown up a few days before coming to camp, don’t you think the parents should have told us something? I do know that most schools have a Rule that says students have to stay out of school for at least 24 hours after their last symptom. Honestly, I thought that was common knowledge but I guess not. I am starting to have a few symptoms of a virus, and I really hope that I don’t get sick because of a parents lack of common sense.