My Son Aged 5 Years Has Been Running Fever For

My son aged 5 years has been running fever for last 10 days. Her fever ranges from 99 - 100.9. The blood count is normal and typhoid test is negative. Her fever goes down with Paracetamol 650 and resuface once effect gors off. Doctor put him augumentin duo as she suspeted infection but it does not seem to be working. She has normal apetite and no aches or tiredness. Somehow fever is not going down, no irritation in urine though urine test has not been done as of now. What could it possibly be?