A febrile seizure is a convulsion in a child with a fever (high temperature). They can occur in up to 1 in 20 children aged between 6 months and 6 years old. Febrile seizures usually last around 1 to 2 minutes with loss of consciousness, but nearly all children will recover quickly, regardless of the cause. Influenza itself can cause fever and results in more febrile seizures than vaccination. In one study, more than 1 in 20 children hospitalised with the flu in Australia had a febrile seizure. In comparison, only 1 in 20,000 children will have a febrile seizure related to fever following a flu shot.