BACILLI OF THE COLON-TYPHOID-DYSENTERY GROUP 713 



16 cases. Such investigations amply prove that even local epidemics 

 may be caused by a considerable number of different organisms. In 

 one case, as a matter of fact, he found two different types in the same 

 patient. Studying family epidemics at the same time, he usually found 

 one and the same type in a single family, but in six families in which 

 there were 25 patients he found two different types. 



As we shall see, dysentery is transmitted by much the same agencies 

 which are responsible for transmission of other intestinal diseases, 

 typhoid, paratyphoid, etc., and in consequence, sanitary and other con- 

 ditions which bring about one disease give rise to cases of the other. 

 It is a noticeable feature of the outbreaks of intestinal disease which 

 occurred in the Allied Armies during the late war that every outbreak 

 of dysenteric maladies was accompanied by enormous numbers of mild 

 diarrheal conditions. This is mentioned by Vincent and Muratet for 

 the French and British Armies, and was noticed by us during the out- 

 break of similar conditions among the American troops in July, 1918. 

 At such times the intestinal disturbances are almost universal among 

 troops, taking, in most, the form of a mild temporary and recurring 

 diarrhea, in others a more severe diarrhea with fever, and in others, 

 again, severe symptoms of typical dysentery. Bacteriological analysis 

 of large numbers of cases is next to impossible under such conditions, 

 but even the limited number made during the late war, at least in the 

 zone of the American Armies showed that all the known varieties of 

 intestinal invaders, typhoid, paratyphoid and the various dysentery 

 bacilli, played a role in the outbreaks. It is not at all impossible that 

 many of the mild cases may have been true dysentery or even true 

 typhoid, modified by increased natural resistance and by vaccination in 

 the men. On the other hand, it is also quite likely, in fact is the view 

 we favor, that the large majority of the mild cases which constituted 

 perhaps 90 per cent of the total, represented infections by various other 

 bacterial agencies originating in the massive infection of food and water 

 with fecal organisms, the result of open latrines, limited water supplies 

 and active fly transmission. 



The most severe epidemics are probably those due to the Shiga 

 bacillus. However, the Flexner bacilli have been known to cause con- 

 siderable epidemics in southeastern Europe and in parts of Asia, in the 

 Philippines, Japan, China and Ceylon. The Strong bacillus has 

 been known to cause disease in the Philippines and the "Y" bacillus 

 has been found rather frequently in milder outbreaks and in sporadic 

 cases especially in the United States. The " Y" bacillus has been par- 



