Electron microscopic demonstration of a new virus isolated from a patient with SMON

The first successful electron-microscopic observation of a virus isolated from a patient with SMON was performed. The morphological and developmental characteristics of this virus suggests that this type of virus has not been isolated from humans. Hence, it is considered that the virus observed is of a new type and presumably the causative agent of SMON. The author wishes to express his profound thanks to Prof. TADASHI OFUJI for painstaking proof reading of the manuscript and also acknowledgement is due to Mr. NOBUO HAYASHI, Mr. NOBORU SAIHARA, Mr. TAKASHI NAKAMURA and Miss TOSHIYO OMIZU for their technical assistance of electron microscopy.