CHAPTER XIII 

 DYSENTERY— CHOLERA 



Dysentery 



The dysentery bacillus was discovered by Shiga in 

 Japan, and by Flexner in the Philippines. It is a 

 Gram-negative, non-motile bacillus, somewhat smaller 

 than the typhoid bacillus. Two main varieties are en- 

 countered, those which ferment mannite (a kind of 

 sugar) and those which do not. 



Acute dysentery, in this climate, is usually due to the 

 dysentery bacillus or some closely related variety. 

 In tropical countries a form of chronic dysentery is due 

 to organisms called ameba% and it is, therefore, customary 

 to speak of ^'bacillary dysentery" and ''amebic dysen- 

 tery." The usual summer diarrheas, however, are not 

 due to dysentery bacilH. 



Like typhoid fever, bacillary dysentery Is due to the 

 swallowing of bacilli which have come from the fecal 

 discharges of another person. Sometimes these bacilli 

 are carried cjuite directly, sometimes indirectly, on food 

 and drink. Occasionally the germs are carried by flies. 



Bacillary dysentery affects especially the .mucous 

 membrane of the large intestine. In mild cases only the 

 superficial portion is involved, but in severe cases deep 

 ulceration may occur. The stools are at first fecal, but 

 soon become nothing but mucus and serum. The mucus 



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