Influenza Virus Antigen in Postencephalitic Parkinsonism Brain

Abstract
Brains of six patients with postencephalitic parkinsonism were examined for influenza virus antigen by direct immunofluorescence. Tissue sections were exposed to fluorescein-conjugated globulin directed against the NWS, WSN, WS, and PR8 strains of influenza A0, the ribonucleoprotein of the WSN strain, the swine strain of influenza A, the Japan strain of influenza A2, the Lee strain of influenza B, measles, and herpes simplex virus. Intranuclear fluorescent antigen was detected in hypothalamic and midbrain sections prepared from all six cases after staining with antibody to the two neurotropic influenza A0strains (NWS and WSN) and to the ribonucleoprotein of the WSN strain. No fluorescence was observed after staining of similar sections prepared from the brains of five patients with idiopathic Parkinson disease with labeled influenza NSW antiserum.