Since there is rash and fever it can
he herpes or shingles
, EBV or mono, CMV or cytomegalovirus, staphylococcal skin infection, HIV, gonorrhea, syphilis, or Lyme’s disease. It can also be chicken pox and measles but appears to be less likely. Please take him to a doctor for diagnosis and treatment. Meanwhile, given him small frequent meals and plenty of fluids. Take care!