By 7 years of age, 3% to 4% of children have 1 or more febrile seizures (Nelson and Ellenberg 1978; Verity and Golding 1991) in the United States, South America, and Western Europe. However, the incidence varies in other parts of the world and higher rates have been noted (Finland 6.9%, India 5% to 10%, Japan 8.8%, and Guam 14%). Febrile seizures are slightly more common in boys and in black (4.2%) versus white (3.5%) North American children (Nelson and Ellenberg 1978).
Risk factors for a first febrile convulsion have been studied in comparison with age-matched febrile and afebrile controls (Bethune et al 1993). The risk of a first febrile seizure is about 30% if a child has 2 or more of the following independent risk factors: (1) a first- or second-degree relative with febrile seizures, (2) delayed neonatal discharge of greater than 28 days of age, (3) parental report of slow development, and (4) day care attendance. Age younger than 18 months at the time of a child’s first febrile seizure and family history of febrile seizures were confirmed as risk factors for recurrence in a Greek study (Pavlidou et al 2008). It may be reasonable to offer anticipatory guidance (familiarization with febrile seizures, first aid, and types of management) to families at high risk.
For 7 years after a first “simple” febrile seizure, children have the same health care utilization as age-matched febrile and afebrile controls, except for a minor increase in referrals to ear, nose, and throat services shortly after the febrile seizure (Gordon et al 2000). Children with febrile seizures do not seem to be more vulnerable to illness. In addition, their parents apparently are not compelled by concern about the child’s health to excessively consult a physician.