Three patients with Reye's syndrome or encephalopathy with fatty degeneration of the viscera were found to have a prior infection with parainfluenza virus types 2 or 3. Virus isolation was achieved in two patients with serum complement fixation and with hemagglutination inhibition titer elevations in the third patient. It is suggested that the subsequent development of Reye's syndrome in these three patients was a directly related sequela of the parainfluenza infection.
Powell HC, Rosenberg RN, McKellar B. Reye's Syndrome: Isolation of Parainfluenza VirusReport of Three Cases. Arch Neurol. 1973;29(3):135–139. doi:10.1001/archneur.1973.00490270017001