My 3 years old son is having high fever (104 degree F) for the last two days. His blood test showed leukocyte count as 32, 500/cu. Mm, neutrophils - 86%, lymphocytes - 8%, monocytes - 6%, eosinophilia & basophils - 0%, platelets - 4.03 lakhs, ESR - 47 mm (1st hour Westergren method), with reactive lymphocytes present and a CRP of 62.8 mg/L and no MP found. His urine test showed no pus cells and red blood cell (RBC). Last month also he had fever, which went up to 102/103 degree F and was given Paracetamol and Taxim -O and he was cured. What should be the line of treatment now.