ACUTE ANTERIOR POLIOMYELITIS 915 



virus independently, succeeded in transferring the disease from one 

 animal to others, demonstrated that the virus could pass through the 

 pores of a Berkefeld filter, and showed that the virus was present in 

 the salivary glands a fact which may prove of great importance in 

 possibly establishing a clew to the mode of contagion among human 

 beings. The same authors, as well as Flexncr and Lewis, were able to 

 show that the virus was preservable under glycerin for as long as ten 

 days and retained its virulence for from seven to eleven days when 

 dried. What has been said concerning infantile paralysis may also be 

 taken to apply to Landry's paralysis. From a typical case of Landry's 

 paralysis in an adult the writer succeeded in obtaining typical poli- 

 omyelitis in monkeys at Stanford University in 1912. The clinical 

 diagnosis in this case was made by Wilbur. The disease in the mon- 

 keys was typical of poliomyelitis and the histological sections showed 

 the typical lesions. 



According to Flexner and Lewis the virus remains active, when 

 frozen, for as long as forty days, but is extremely sensitive to heat, 

 being destroyed by a temperature of from 45 to 50 C. maintained for 

 thirty minutes. 



Experiments aimed at the isolation or even morphological detection 

 of a parasite in the virulent material have been entirely without suc- 

 cess until recently. Bacteria which in the past have been isolated from 

 nerve substance and spinal fluid in cases of poliomyelitis can of course 

 be excluded from etiological significance by the recent determination of 

 the filtrability of the virus as determined by Flexner and Lewis, and 

 Landsteiner and Levaditi. Small coccoid forms in smears from the 

 nerve tissue recently described by Proescher 9 are of very uncertain 

 significance. The streptococci recently described by Kosenow are, 

 most probably, secondary invaders. The most important contribution 

 which has been made in the solution of this problem is that of Flexner 

 and Noguchi. 10 These investigators placed small bits and emulsions of 

 the brain of monkeys, dead of poliomyelitis, in high tubes containing 

 human ascitic fluid together with a piece of fresh sterile rabbit kidney. 

 In all essentials the method was that followed by Noguchi in his culti- 

 vation of Treponema pallidum. It was necessary to use fresh unheated 

 ascitic fluid. Heat sterilization rendered it unsuitable. 



By this method, after five days opalescence appeared about the 



'Proescher, N. Y. Med. Jour., 1913. 



10 Flexner and Noguchi, Jour, of Exp. Med., xviii, 1913. 



