Botulism. 



ioi 



and guinea pigs are immediately injected for the demonstration of 

 toxin and determination of its type. No test is considered positive 

 unless the broth culture within the sealed tube contains a virulent 

 botulinus toxin at the time the tube is broken. 



This technic, because it eliminates all possibility of con- 

 tamination of the contents of the tubes after they have been 

 subjected to the required amount of heat, ensures that any bacteria 

 which are alive within the tube must be the growth from bacteria 

 or spores which have survived the heating process. It also demon- 

 strates beyond any possibility of doubt not only when the botulinus 

 spores have survived the given exposure to heat but whether they 

 have retained their ability to form toxin. 



