SUMMARYObjective: To explore if afebrile seizures associated with minor infections are a single category of seizure, or a set of different kinds of seizures. Methods: We conducted this prospective cohort study on three kinds of first afebrile seizure: first afebrile seizure associated with gastrointestinal infection (AS-GI), first afebrile seizure associated with nongastrointestinal infection (AS-nGI), and first unprovoked seizure (US). The Kaplan-Meier estimate risks of recurrent seizures were analyzed and compared pairwise. The characteristics of recurrent seizures were also compared pairwise. Results: The Kaplan-Meier estimate risks of recurrent seizure at 2 years of the AS-GI, AS-nGI, and US groups were 6.9%, 23.7%, and 37.8%, respectively. The pairwise differences were significant between the AS-GI and US groups (p < 0.001) and between the AS-GI and AS-nGI groups (p = 0.001), but not significant between the US and AS-nGI groups (p = 0.066). Among unprovoked subsequent seizures in patients with recurrence, the pairwise differences were significant between the AS-GI and US groups (p < 0.001) and between the AS-GI and AS-nGI groups (p = 0.005), but not significant between the US and AS-nGI groups (p = 0.417). Significance: Afebrile seizures associated with minor infections are indeed of two distinguishable kinds: AS-GI, if free of risk factors such as a family history of epilepsy, had a better prognosis and should be categorized as an acute symptomatic seizure, whereas patients with first AS-nGI, like patients with first US, may have recurrent unprovoked seizures, which suggests this category's essential difference from AS-GI. The minor infections include gastrointestinal infection, respiratory infection (usually of the upper respiratory tract), and others of uncertain origin. For gastrointestinal infection, there is a concept of "benign convulsion with mild gastroenteritis (CwG)." The word "benign" indicates a good prognosis: a very low chance of having unprovoked seizures later in life. [4][5][6] In addition, CwG seems to be a new entity, which was more likely to be categorized as situation-related seizures than epilepsy, although it is not described in the classification of the International League Against Epilepsy (ILAE). 4,5,7 However, for afebrile seizure induced by nongastrointestinal infection, the risk of recurrence of unprovoked seizure is much higher than that for afebrile seizure induced by gastrointestinal infection, 1 whereas another study 3 shows that only this kind of first seizure and first unprovoked seizure would have subsequent unprovoked seizures. This evidence suggests that seizures caused by gastrointestinal infection and nongastrointestinal infection are essentially different: the former is probably in the category of situation-related seizures, whereas the latter may have a likeness to unprovoked seizure.Therefore, we designed this prospective cohort study on three kinds of first afebrile seizures: first afebrile seizure associated with gastrointestinal infection (AS-GI), first afebril...