CHAPTER XXI. 



Typhoid fever — Study of the organism concerned in its production — ■ 

 Bacterium, coli commune — Bacillus dysenterix — Its resemblance to 

 the bacillus of typhoid fever — Its morphological, cultural, and 

 pathogenic properties — Its differentiation from lacillus typhosus — 

 Methods of isolating the typhoid bacillus. 



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- 



Fia. 71. Fig. 72. 





Sadaus 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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