TETANUS 



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Formerly tetanus was supposed to be due to injury 

 to the nerves, and the idea that it is an infectious 

 disease, due to the introduction of a specific bacillus 

 into a wound, had not been entertained prior to the 

 demonstration that the symptoms which characterise 

 this disease may be produced in the lower animals by 

 inoculating them with garden earth or with a pure 



FIG. 12. Bacillus of tetanus ; magnified 1000 diameters. Spores are seen 

 at the ends of some of the bacilli. 



culture of the tetanus bacillus. The nervous symp- 

 toms are now known to be due to the fact that the 

 tetanus bacillus produces a deadly poison (toxin) which 

 has a special affinity for the nervous tissues. When 

 a barefooted boy steps upon a rusty nail and, as a re- 

 sult of the penetrating wound inflicted by it, develops 

 tetanus, this result is not due to the fact that the nail 



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