ACUTE ANTERIOR POLIOMYELITIS 667 



We have few data which throw light upon possible immunity to the 

 disease. Repeated attacks of the disease in the same human being 

 have not been noted; but this, as Flexner and Lewis point out, may be 

 due to the fact that the epidemics are rare, and individuals once afflicted 

 have passed beyond the susceptible age by the time of the second 

 epidemic. As a matter of fact, however, these workers have not suc- 

 ceeded in reinfecting monkeys that had recovered, and incline to the 

 belief that one attack protects against subsequent infections. 



Up to the present time monkeys and rabbits only have responded to 

 experimental inoculation; numerous attempts made upon a variety of 

 other animals have been without success. 



In chickens a disease has been observed similar in many ways to 

 poliomyelitis, but further study has shown this to be a polyneuritis of 

 entirely different nature from infantile paralysis. 



Of other animals besides monkeys, rabbits only have been success- 

 fully inoculated with this disease. Transmission to these animals was 

 first reported by Kraus and Meinicke x and later by Lentz and Hunte- 

 muller. 2 Marks 3 has studied the disease in rabbits thoroughly, and con- 

 cludes that there is no doubt that the virus can be cultivated through 

 a limited number of generations in rabbits. He was able to transmit 

 to monkeys from rabbit material. The disease, however, does not 

 resemble that of man or monkeys clinically and no definite lesions of 

 the central nervous system are present. The rabbits seem perfectly 

 well for six or seven days, when rapid weakness and death in convulsions 

 occur. 



1 Kraus und Meinicke, Deut. med. Woch., xxxv, 1909. 



2 Lentz und Huntemiiller, Zeitschr. f. Hyg., Ixvi, 1910, 



3 Marks, Jour, of Exp. Med., xiv, 1911, 



