CHAPTER XXXVIII. 

 BACILLUS MALIGNI (EDEMATIS. 



Introduction. 



Section I. Experimental inoculation, p. 561. 



1. Susceptible animals, p. 561. 2. Methods of infection, p. 562. 3. Symptoms 

 and lesions in experimental animals, p. 563. 

 Section II. Morphology, p. 563. 



1. Microscopical appearance and staining reactions, p. 563. 2. Cultural charac- 

 teristics, p. 564. 

 Section III. Biological properties, p. 565. 



1. Vitality and virulence, p. 565. 2. Toxin, p. 565. 3. Vaccination, p. 567. 

 4. Serum therapy, p. 568. 5. Agglutination, p. 568. 



THE bacillus of malignant oedema (Fr. Vibrion septique) is the oldest known 

 anaerobic pathogenic micro-organism. In 1887 Pasteur determined its 

 morphology and biological properties and described, as " acute experimental 

 septicaemia," the disease which follows the introduction of the organism into 

 the sub-cutaneous cellular tissue of laboratory animals. Chauveau and 

 Arloing showed that the bacillus of malignant oedema is the ordinary cause 

 of the rapid gaseous gangrene of man * (gangrenous septicaemia). Krannhals 

 attributed " rag-pickers' disease " to this organism. German writers describe 

 the organism under the name " Malignes Odem." 



Certain traumatic gangrenes of domestic animals are also caused by the 

 bacillus of malignant oedema. 



The bacillus of malignant oedema is very widely distributed outside the 

 body. In the spore form it is found in garden soil, in dirt from the street, 

 in the mud of different waters, etc. It occurs as an harmless saprophyte 

 in the intestine and in the excreta of man and animals. After death the 

 bacillus may pass from the intestine into the blood stream : this infection 

 of the blood stream takes place very rapidly in animals which have died of 

 anthrax. 



SECTION I. EXPERIMENTAL INOCULATION. 

 1. Susceptible animals. 



Most animals are susceptible to infection with the bacillus of malignant 

 oedema and guinea-pigs and mice particularly so : one-millionth of a drop 

 of an infected exudate is sufficient to kill a guinea-pig (Davaine). 



1 The bacillus of malignant oedema is not the only cause of gangrene. In Chap. XXXIX. 

 a number of other anaerobic organisms which may be concerned in gangrenous conditions 

 are described. 



2N 



