CHAPTER XX. 



Typhoid fever Study of the organism concerned in its production 

 Its morphological, cultural, and pathogenic properties Bacillus 

 coli Bacillus paratyphosus Its resemblance to Bacillus typhosus. 



BACILLUS TYPHOSUS. 



THE organism discovered in the tissues of typhoid 

 cadavers microscopically by Eberth (1880-81), and 

 subsequently isolated in pure culture and described by 

 Gaffky (1884), is now generally recognized as the etio- 



FIG. 70. FIG. 71. 



Bacillus typhosus, from culture Bacillus typhosus, showing flagella 



twenty-four hours old, on agar- stained by Loffler's method, 



agar. 



logical factor in the production of typhoid fever. It 

 may be described as follows : 



It is a bacillus about three times as long as broad, 

 with rounded ends. It may appear at one time as very 

 short ovals, at another time as long threads, and both 



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