my son, who is 2, has had to bouts of very high fever above 104 and as high as 105.3. All blood work and cultures came back negative. He does have a history of MRSA infections, but none was found during the fevers. He has had a complete immunology work up, and everything was fine. The first time with the fever was the beginning of May and then again last week. Should I be concerned? His pediatrician says it is probably just viral.