TOXIN PRODUCTION 455 



spores. It requires an alkaline medium, no growths occur on acid 

 media, and 5 to 6 per cent, of sodium chloride also prevents its multipli- 

 cation. The spores are not very resistant and are destroyed if exposed 

 one hour to 80 C. They are killed by 5 per cent, carbolic acid within 

 twenty-four hours. If protected against air and sunlight they remain 

 alive for a long time either in moist or desiccated condition. The 

 organism, however, dies comparatively quickly in glucose gelatin and 

 the cultures must be transferred every three or four weeks. It is 

 also necessary to transplant a larger mass of the sediment from such 

 cultures. The culture media should always be distinctly alkaline 

 and not exposed to temperatures above 25 C. 



Animals Susceptible. If small amounts of cultures (0.0003 to 0.001) 

 are injected into rabbits the animals may die within thirty-six to 

 forty-eight hours. Sometimes they live three to four days, then 

 become paralytic and die shortly after these symptoms have appeared. 

 If the cultures are introduced into the stomach the effect is slow and 

 uncertain. Doses of 5 to 10 c.c. of a bouillon culture may kill rabbits 

 within forty-eight hours. At times a slow cachexia develops, and the 

 animals only die after a number of weeks. Guinea-pigs are very sus- 

 ceptible to minimal doses ; they show aphonia, forced respiration, great 

 dyspnea, and death. Mice and monkeys are not very susceptible. 

 Dogs, chickens, and cats are refractory, and can withstand large doses 

 given repeatedly, but they may show some transitory paretic symptoms. 



Toxin Production. Van Ermengem believes that the symptoms due 

 to the Bacillus botulinus in man and in artificial animal inoculation 

 are due exclusively to intoxication without any multiplication of the 

 bacillus in the infected organism. He classifies the Bacillus botulinus 

 as a pathogenic or toxigenic saprophyte, and likens its action to that 

 of the large poisonous fungi which produce disease and death by the 

 amount of already formed toxin introduced with them into a suscept- 

 ible animal. The botulismus toxin which affects susceptible animals 

 not only in subcutaneous or intravenous injections, but also if intro- 

 duced into the stomach, is not very resistant. It is destroyed if 

 heated to 80 C. for one hour; it is almost instantaneously destroyed 

 by a 3 per cent, carbonate of soda solution; it is somewhat more 

 resistant toward acid and soon succumbs to the effect of light and 

 air. This toxin, like the tetanus toxin, is fixed by emulsions from 

 the central nervous system, by lecithin, cholesterin, fatty substances. 

 Van Ermengem recommends the following as prophylactic measures 

 against infection with the Bacillus botulinus: Articles of food which 

 in a raw condition may be easily decomposed, such as ham, sausages, 

 salted fish, should not be eaten raw. All foods which give off a smell 

 of butyric acid are suspicious and may contain the Bacillus botulinus. 

 Pickled meat or fish should be soaked before use in a not less than 

 10 per cent, salt solution, which will destroy the Bacillus botulinus. 



Kempner has prepared an antitoxic botulinus serum which proved 

 efficacious in protecting animals. 



