Seizure precipitated by febrile infection Febrile seizure outside the age of 3 months to 6 years 2020-03-18T14:04:47Z Some but not all people with the epilepsy syndrome of Febrile Seizures Plus have these types of seizures. Any type of seizure (most often a generalized tonic-clonic seizure) occurring with fever (at least 38.0 degrees Celsius) but in the absence of central nervous system infection, severe metabolic disturbance or other alternative precipitant in people beyond the typical arrange of 3 months-6 years with no prior history of afebrile seizure.