SPORE-FORMING PATHOGENIC ORGANISMS 81 



lymph and Fuller's earth have occasioned tho disease. 

 The spores can on occasion live through the operations 

 involved in the manufacture of gelatin, and injection of 

 contaminated gelatin has produced tetanus. 



The organism is pathogenic to man, the horse, guinea- 

 pig, mice, and rabbit; birds are but slightly susceptible. 

 The bacilli remain in the locality of the site of inoculation 

 and in the nearest lymph glands, symptoms being caused 

 by absorption of the toxins. In the development of the 

 disease, damage to local tissues and prevention of phago- 

 cytosis are the most important factors, the latter being 

 allowed by the extraneous organisms which gain access 

 with the tetanus bacilli. The spore, if freed from toxin 

 by simple washing, is readily disposed of by phagocytosis. 



Usually fifteen days elapse between infection and the 

 appearance of symptoms, but they may occur in man in 

 two days, or not till after twenty-seven days. 



It is rarely that drumstick spores can be found in 

 material from a wound, and should any be found, the 

 existence of other Gram-positive bacilli growing terminal 

 spores must not be overlooked. 



Toxins. Grown anaSrobically in glucose broth, the 

 tetanus bacillus produces a powerful extracellular toxin, 

 of the constitution of which little is known. There is a 

 substance producing the characteristic spasm (tetano- 

 spasmin), a hsemolysin (tetanolysin), and some albumoses 

 to which Sidney Martin ascribes the fever of tetanus. 

 The toxin is readily destroyed by heat and light, and di- 

 minishes in toxicity with keeping. Tetanus toxin is rapidly 

 fixed by the tissues of the central nervous system, and 

 travels from the wound by way of the nerve trunks. 



Antitetanic Serum. In Roux and Vaillard's process, 

 virulent tetanus bacilli are cultivated in broth in an 

 atmosphere of hydrogen. After about fourteen days' 

 growth, the culture is filtered through a porcelain filter 

 to free it from bacilli. Injections are then made into 

 horses with this toxin daily, subcutaneously or intra- 

 venously, starting with 1 c.c. of iodised toxin, gradually 

 increasing the dose until the pure toxin can be injected 

 without danger, the treatment lasting about three months. 

 The serum is standardised. The results attending the 

 use of this serum have been less satisfactory than those 

 obtained with antidiphtheria serum, as the disease is only 



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