Neurologic Manifestations of Novel Influenza A (H1N1) Virus Infection in Childhood

The neurologic manifestations and prognoses of a novel influenza A (H1N1) virus infection in previously healthy children were evaluated. Nose and throat swabs were retrieved from all patients who met the criteria of influenza-like illness. A real time reverse-transcriptase polymerase chain reaction assay was used to confirm the novel influenza A (H1N1) virus. This viral infection was evident in 240 children between October 10 and December 22, 2009. Neurologic findings were evident in 17 (7.08%) patients, aged between 4 months and 8 years. Nine were boys. Five patients manifested simple febrile seizures, seven manifested complex febrile seizures or additional afebrile seizures, and three manifested encephalopathy. Febrile status epilepticus and flaccid paralysis were diagnosed in one patient each. All were treated with oseltamivir. Fifteen of 17 patients demonstrated complete recovery. One undergoing follow-up with a diagnosis of Guillain-Barré syndrome manifested sequelae. One patient died because of septic shock and disseminated intravascular coagulation. We suggest that neurologic manifestations occur quite often in children aged less than 5 years with novel influenza A (H1N1) virus infection. Most infections were benign, although a severe course is possible, and sequelae may be encountered.