308 PROCEEDINGS OF THE INDIANA ACADEMY OF SCIENCE. 



disease and how it may be spread in the immediate neighborhood of the in- 

 fected one. 



Flexnor, Clark, and l-'razer have apparently positively demonstrated the 

 part of the healthy "carrier" by infecting a monkey with washings of the mu- 

 cous membrane of a parent of a child who was suffering from the disease. The 

 question arises; are adulrs relatively' immune because they have had the 

 disease in a mild form in childhood. Likewise, this may explain the occur- 

 rence of few cases of the disease in densely inhabited localities. 



Osgood and Lucas experimentally demonstrated the presence of the 

 virus on the mucous membrane of a monkey five and one-half months after 

 apparent recovery, They also proved its presence in a chronic "carrier" 

 in man. Kling, Pettersson, and Wernstadt corroborated these latter find- 

 ings. 



In humans as well as in monkeys stomach and intestinal symptoms ofteu 

 occur previous to parah^sis. Medin, Wickman, Krause, and Richardson, 

 because of these symptoms, were lead to believe that there were other av- 

 enues of entrance for the virus than through the air passages of the nose and 

 throat. However, Romer and Joseph called attention to the fact that mon- 

 keys which were injected intracrainally develop gastro-intestinal symptoms. 



The virus is widely disseminated in th(> l)ody. It is constantlj' found in 

 the central nervous system and cerebro-sj)inal fluid, mucous membrane of 

 nose and throat, mesentery glands, lymph nodi-s, intestines and it has been 

 found in the general circulating blood and internal organs. 



Poliomyelitis has a seasonal prevalence which does not correspond to 

 that of diseases spread by secretions or excretions of the nose and mouth. 

 Its seasonal prevalence is during summer and fall and because of this fact 

 it was thought that the disease was insect-borne. Experiments directed 

 along these lines by Flexnor and (^lark showed that flies which were allowed 

 to come in contact with infected spinal cord couhl carry the virus at least for 

 48 hours. Flies that were caught in sick rooms according to Kling, Pet- 

 tersson, and Wernstadt could not produce infection. Howard and Clark 

 were able to ex])erimentally i)roduce the disease by injecting filtrates made 

 from bed-bugs seven days after they were permitted to suck the blood from 

 infected monkeys. However, transmission by the bite of bedbugs, mos- 

 quitoes, and lice proved uniformally negative. Rosenau and Brues were 

 able to successfully transmit the virus from monkey to monkey by the bite 

 of the stable fly {Slontaxy^i calcitruns). They believe this fly is the inter- 

 mediate host. Kling and Levaditi seem to have positively proven that the 

 disease is not in.sect-borne. They had occasion to allow flies, bedbugs, and 

 mosquitoes to feed upon infected material and in no case were they able to 

 j)roduce the disease by injecting emulsions of them into monkeys. Also, 

 in opposition to this view, is the fact that in order to infect a monkey from the 

 blood of a monkey suffering from the disease Flexnor and Lewis had to take 

 twenty cubic centimeters; with two cubic centimeters they failed. Leiner 

 and Wiesner made six attempts using defibrinated monkey blood taken after 



