654 • Typhoid Fever 



whether they are to be regarded as variations from the type species 

 or separate and distinct organisms. The fact that some of them are 

 associated with serious and fatal disorders — ^paracolon bacillus and 

 bacillus of psittacosis— proves them, at least, to be important. 

 Buxton* summarizes the main points of difference as follows: 



B . coli com- 

 munis Intermediates B. typhosus 



Coagulation of milk + — — 



Production of indol + — — 



Fermentation of lactose with 



gas + - - 



Fermentation of glucose with 



gas + + - 



Agglutination by typhoid 



serum — — + 



The characteristics of the three groups as shown by the fermenta- 

 tion-test stand thus:t 



Gas upon Gas upon Gas upon 



dextrose lactose saccharose 



Bacillus typhosus — . — I 



Intermediates -f- ~ — 



Bacillus coli communis + + — 



Bacillus coli communior -|- -J- + 



Buxton finds those pathogenic for man clinically divisible into 

 three groups, as follows : 



(a) The Meat-poisoning Group. — This includes Bacillus enteritidis 

 of Gartner and others. The symptoms begin soon after eating the 

 poisonous meat, and are toxic. Bacilli quickly invade the body. 

 The illness continues four or five days, after which recovery is quick. 

 In a few cases death has occurred on the second or third day. 



{b) The Pneumonic or Psittacosis Group. — Psittacosis is an epi- 

 demic infectious disease with pneumonic symptoms and a high 

 mortality. Its origin has been traced to diseased parrots, and from 

 them Nocard isolated Bacillus psittacosis, supposed to be the cause 

 of the disease in man. Later epidemics were studied by Achard 

 and Bensaude. 



(c) The Typhoidal Group. — The organisms to be included in this 

 group occasion symptoms closely resembling typhoid fever, though 

 they differ biologically from the typhoid bacillus, and do not agglu- 

 tinate with t3rphoid serums. 



It is thus evident that some of the intermediates occasion symp- 

 toms resembling typhoid fever, while others occasion symptoms 

 widely differing from it. It is suggested that to the former the 

 term paratyphoid bacilli be applied, while the latter are known as 

 paracolon bacilli. 

 Achard and Bensaude,! Johnson, Hewlett, and Longcope,§ 



* "Journal of Medical Research," vol. vin, No. i, June, 1902, p. 201. 

 t Hiss and Zinsser, "Text-book of Bacteriology," 1910, p. 429. 

 + "Soc. Med.,"Nov., 1896. 

 § "Amer. Jour. Med. Sci.," Aug., 1902. 



