It went through my daycare 2 years ago and I went by my fever rule because the children all came down with high fevers and 3 out of 5 had terrible spots and rashes, mostly in their mouths were the sorest ones. Then they didn't want to eat so it was best for them to be at home. They were miserable. So I asked the parents to keep the children home if they had open sores and 24 hours after their fevers returned to normal which is my policy for any sickness. Once one child caught it he exposed it to the entire daycare so they all got it within the same week.