Kevin's Rash

Kevin, 5, was sick on Sunday...didn't eat or drink or get off the couch practically all day. So I kept him home Monday. He complained of a few itchy spots but I just assumed they were mosquito bites. That night he comes into our room complaining again, I notice several blotches,and it dawns on me that he has 5th's disease. (There I am at 3:45 googling and reading about his textbook case.) I kept him home one more day but this morning I gave him antihistamine and sent him to school with a rash and a note since Fifth's is no longer contageous once the rash appears. I'm reading that this rash could last up to 3 weeks! THREE WEEKS! I hope not!