Classic symptoms of the “flu” caused by influenza include fever, coryza, body aches, and cough. Central nervous system (CNS) involvement is unusual. Wiley in his review of emerging infections of the CNS describes three conditions that are necessary for the Influenza virus to go beyond its usual pulmonary presentation to causing severe neurologic disorders . The virus must evade its local site of replication and reach the brain. There can occur by direct infection of nerve endings, specifically the olfactory nerve which has nerve endings in the nasal cavity . How this occurs is unclear, and it is not specific for the Influenza virus as it has been described for other viruses such as adenoviruses, parainfluenza viruses, and West Nile Virus. Secondly, the virus has to infect neurons. Influenza virus can bind to neural cells by sialic acid glycosylation or through endocytosis. Once bound to neurons, neuronal proteases can facilitate cell entry, and utilize cellular machinery to replicate . Lastly the virus must survive immune response manifested, in part, by cytokine release. Lee in his review of acute encephalopathy secondary to Influenza note very high levels of cytokines and chemokines in both the blood and cerebral spinal fluid. These high levels seem to correlate with disease severity and neurologic outcome.