15 month old baby has fever, all pathological tests are normal?

Today is the fourth day, my baby who had febrile seizure on day 1 has still some fever close to 102 degree C. She is continuously given paracetamol syp. every 6 hours. All tests done like urine routine, malaria, blood count, and meningitis are normal. Doctors say it may be a viral infection (non-specific). How long it would take for such a fever to subside, any feedback with references would be greatly appreciated.