STUDY OBJECTIVE: We assess the prevalences of bacterial meningitis and herpes simplex virus meningoencephalitis (HSV-ME) in children with a complex febrile seizure and determine these prevalences in the subgroup of children with a clinical examination result not suggestive of meningitis or encephalitis. METHODS: This multicenter retrospective study was conducted in 7 pediatric emergency departments (EDs) in the region of Paris, France. Visits of patients aged 6 months to 5 years for a complex febrile seizure from January 2007 to December 2011 were analyzed. We defined a subgroup of patients whose clinical examination result was not suggestive of meningitis or encephalitis. Bacterial meningitis and HSV-ME were sequentially sought for by analyzing bacteriologic and viral data at the visit, looking for data from a second visit to the hospital after the index visit, and telephoning the child's parents. RESULTS: From a total of 1,183,487 visits in the 7 pediatric EDs, 839 patients presented for a complex febrile seizure, of whom 260 (31.0%) had a lumbar puncture. The outcomes bacterial meningitis and HSV-ME were ascertainable for 715 (85%) and 657 (78.3%) visits, respectively, and we found 5 cases of bacterial meningitis (0.7% [95% confidence interval [CI] 0.2% to 1.6%]) and no HSV-ME (0% [95% CI 0% to 0.6%]). Among the 630 visits of children with a clinical examination result not suggesting meningitis or encephalitis, we found no bacterial meningitis (0% [95% CI 0% to 0.7%]) and no HSV-ME (0% [95% CI 0% to 0.8%]). CONCLUSION: In children with a complex febrile seizure, bacterial meningitis and HSV-ME are unexpected events when the clinical examination after complex febrile seizure is not suggestive of meningitis or encephalitis.