We report a three-year-old female with intractable epilepsy post West syndrome whose seizures disappeared following an acute viral infection, without changes in anti-epileptic therapy.The female infant was born at term to a healthy mother after an uneventful pregnancy and delivery. At the age of five months, she developed intractable brief tonic spasms which had a series of infantile spasms, and an electroencephalogram indicated hypsarrhythmia. She was diagnosed with West syndrome. The seizures were uncontrollable with conventional therapy, including ACTH, vigabatrin, sodium valproate, clonazepam, zonisamide, and ketogenic diet. Daily multiple generalized tonic seizures and brief tonic spasms were observed before an episode of viral infection.At the age of three years, the intractable seizures disappeared after a febrile rash illness due to human herpesvirus 7 (HHV-7) infection, without changes in anti-epileptic drugs.The disappearance of intractable epileptic seizures following acute viral infections might be related to the inflammatory or immunologic processes associated with viral infections. This is the first documented case of spontaneous remission of intractable epileptic seizures following HHV-7 infection.