APPENDIX G. 



EPIDEMIC POLIOMYELITIS. 



WHILE the occurrence of " infantile paralysis " of sudden onset, 

 and affecting especially one or more limbs, has been known since 

 the earliest times, it is only coincident with the modern develop- 

 ments of neurology that the most prevalent type has been 

 recognised to be associated with inflammatory changes which 

 are specially concentrated in the anterior cornua of the spinal 

 cord. The disease is usually sporadic in its incidence, and, as 

 has long been known, in temperate climates it is of most 

 frequent occurrence during the warmer months of the year. It 

 also occurs in an epidemic form. Such outbreaks have been 

 familiar in Norway and Sweden during the last century, but in 

 other countries similar epidemics, limited or extensive, have come 

 under notice. Thus in New York in the summer of 1907 an 

 outbreak of probably over 2000 cases occurred, 762 of which 

 were carefully investigated by a special Commission, and it 

 is from their work that our present knowledge of the 

 disease has been chiefly derived, and many facts regarding its 

 infective nature definitely established. Clinically, the onset of 

 the condition is marked by more or less pronounced fever, often 

 accompanied by sore throat and followed after a few days by 

 signs of paresis and paralysis, and in a relatively small proportion 

 of cases resulting in death. When recovery occurs, many of the 

 paralytic symptoms may pass off, but usually there remains 

 evidence of definite permanent injury to the motor functions 

 of the nervous system. Pathologically, the initial lesions consist 

 in a local or general leptomeningitis with pronounced leucocytic 

 exudation of a polymorphonuclear type into the perivascular 

 lymphatics, the existence of which is reflected in the appearance 

 of such cells in large numbers in the cerebro-spinal fluid. In 

 the cord the inflammatory condition is usually marked in the 

 arterioles of the anterior commissure, especially in the cervical 

 and lumbar regions, and thence passes into the anterior cornua, 



