Neurologic Complications of Influenza and Potential Protective Vaccine Effects

Influenza is a common respiratory infection affecting persons of all ages and results in significant morbidity and mortality. Respiratory complications are well known, but important nonpulmonary complications are less well recognized. Neurologic complications following influenza infection may accompany the acute illness or may be chronic in nature. The acute complications such as seizures, encephalitis, myelitis and Guillain Barre Syndrome are well documented but fortunately are uncommon. However, stroke and dementia are leading causes of death and disability worldwide, and there is increasing evidence linking these devasting illnesses with influenza. In addition, influenza vaccine has been associated with protective effects against stroke and dementia risk.