TYPHOID 177 



Pathogenesis. — In persons affected with typhoid fever the 

 bacUlus is present in immense quantities in the faeces and 

 intestines ; it sets up an inflammation and suppuration of 

 the Peyer's patches, forming ulcers which may become so 

 deep as to lead to perforation. The bacillus is easily de- 

 monstrable in the faeces, but not so readily in the inflamed 

 portions of the intestine, in which it occurs rather sparingly. 

 In the fseces the bacillus is rarely found before the eighth 

 or ninth day of fever, and from observations made by Dr. 

 James Richmond in the pathological laboratory of the 

 Owens CoUege, it appeared that only a few days (from six to 

 ten) after the cessation of the fever the typhoid bacilli were 

 no longer present in the faeces. 



The Eberth-Gaffky bacillus is also found in the mesen- 

 teric glands, the spleen, and sometimes in the blood ; in 

 the intestine it is associated with streptococci and other 

 organisms, and the inflammation set up originally by the 

 typhoid bacillus may be continued by these other organisms 

 after the typhoid bacillus can no longer be found in the 

 faeces. 



Occasionally the sputum (in some cases of pneumo-typhoid) 

 and the urine may contain the typhoid bacillus. 



The injection of the bacilli into the aural vein of rabbits 

 causes death in from twenty-four to twenty-eight hours. 

 Guinea-pigs into which the cultures are introduced by the 

 mouth are also killed. 



The Bacillus coli communis is not found with the Eberth- 

 Gaffky bacillus in typhoid lesions, but it does frequently 

 produce a secondary infection. The two organisms cannot 

 be cultured together in large numbers, as the products of 

 their vital activity are mutually inimical. 



It is a matter of frequent experience that cases of typhoid 

 fever occur after exposure to sewer gas, or vitiated air, which 

 does not actually carry the bacillus, but may produce such 



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