Febrile Seizures By M Cristina Victorio, MD, Akron Children's Hospital Reviewed / Revised Mar 2023 View Patient Education Symptoms and Signs Diagnosis Treatment Prognosis Prevention Key Points More Information Febrile seizures are diagnosed in children 6 months to 5 years of age who have fever > 38 ° C that is not caused by a central nervous system infection and who have had no previous afebrile seizures.