CHAPTER XXII. 



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 seen in the cadavers of typhoid sub- 

 jects by Eberth (1880-81), and subsequently isolated in 

 pure culture and described by Gaffky (1884), is gener- 

 ally recognized as the exciting factor of typhoid, fever. 



FIG. 71. FIG. 72. 



Bacillus typhosus, from cul- Bacillus typhosus, showing fla- 



ture twenty-four hours old, on gella stained by L6 filer's method, 



agar-agar. 



It may be described as follows : 



MORPHOLOGY. 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 forms may occur together. Its 



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