My Child Has A Fever Of 101.5 And Gets These

my child has a fever of 101.5 and gets these splotchy rash marks on his skin and then they go away. This has been coming and going for a few days. It almost seems like the red marks come when he is warm. The red splotchy marks at times have very small white bumps in the middle of the mark. He has not had any vaccines lately and is not allergic to anything that I am aware of. Laundry detergent and things like that have not changed either. Any suggestions?