454 BACILLUS BOTULINUS 



BACILLUS BOTULINUS. 



There is still another form of meat poisoning due to a bacterium, 

 the toxins of which are destroyed by heating. This form of meat 

 poisoning is known as botulismus, or allantiasis. It has been most 

 frequently observed following the ingestion of sausages and pickled 

 or smoked meat. Similar affections have been traced to the con- 

 sumption of fish and they are then spoken of as ichthyosismus. Articles 

 of food through which these intoxications are produced, are generally 

 prepared and kept under conditions which favor the development of 

 anaerobic bacteria; they are consumed raw or imperfectly boiled or 

 cooked. The symptoms of botulism differ from the gastro-intestinal 

 disturbances characteristic of Bacillus enteritidis infection or intoxica- 

 tion and point to nervous disturbances, such as paralysis of the muscles 

 of the eye, double vision, constipation, and enuresis. Diarrhea and 

 vomiting are rare, and if present they are of a transitory character. 

 Other disturbances often noticed are dryness of the buccal and 

 pharyngeal mucosa and redness, disturbance of the voice, and 

 difficulty in respiration. 



Morphology. The Bacillus botulinus was discovered in 1895 in a 

 meat-poisoning epidemic affecting 50 persons by Van Ermengem, who 

 investigated it most thoroughly and furnished the following descrip- 

 tion: It is a strictly anaerobic bacillus, 4 to 6 micra long and 0.9 to 

 1.2 wide; its ends are somewhat rounded off, it forms groups of two 

 or somewhat longer chains; it is sluggishly motile and possesses four 

 to eight very fine flagella, arranged in a peritrichous manner. 



Cultural and Staining Properties. It stains easily and is Gram 

 positive. The growth is most characteristic on glucose gelatin plates, 

 where the young colonies are circular, transparent, slightly yellowish, 

 and composed of coarse granules, which show a constant motility. 

 Zones of liquefied gelatin surround the colonies. The colonies later 

 become larger, brown in color, and opaque, and only the granules at 

 the periphery retain their motility and look like thorny projections. 

 The latter become larger and divide and form digit-like masses and 

 the entire colony resembles a sunflower. Stick or stab cultures in 

 glucose gelatin or agar are not as characteristic. These media become 

 cleft and broken up in consequence of abundant gas formation. The 

 liquefied gelatin later becomes transparent because the growth falls to 

 the bottom as a whitish, flocculent sediment. A large amount of gas 

 composed of hydrogen and methane (CH 4 ) is formed. All cultures 

 give off a smell of butyric acid, but there is no marked fetor. Milk 

 is not coagulated; lactose and saccharose are not fermented. The 

 growth is abundant under anaerobic conditions between 18 to 25 C. ; 

 at 37 to 38.5 C. the growth is scanty, involution forms soon appear, 

 and toxins are no longer formed. In bouillon cultures kept at 37 to 

 38.5 C. the organism forms long, intertwined filaments. The bacillus 

 at medium temperatures forms oval, somewhat elongated, endogenous 



