BACILLUS TETANI 107 



Tetanus Antitoxin. The toxin of the tetanus bacillus is 

 one of the most virulent poisons known. For example, 

 i o o 0*0 o o o cubic centimeter or GTsVoo minim has been known 

 to kill a mouse. It is composed of two parts, one the major, 

 with a primary irritating and secondary paralyzing effect 

 on the central nervous system, and a minor part having a 

 solvent action upon the red blood cells. These poisons 

 develop both in wounds and on laboratory culture media. 

 The methods for procuring this poison are essentially those 

 described under Diphtheria, and similar methods are used 

 to immunize horses against it. The antitoxin is in the 

 immunized horse's serum, and is refined and used in the 

 same general manner as diphtheria antitoxin. The unit in 

 this case is the quantity of antitoxin necessary to neutralize 

 1000 times the smallest dose of toxin required to kill a guinea- 

 pig weighing 350 grams, llf ounces. The conditions of 

 administering antitoxin for tetanus are somewhat different 

 from those in diphtheria. In the latter the poison is largely 

 circulating in the blood, while in tetanus some of it is at the 

 point of infection, some in the muscles and nerves and central 

 nervous system, and the least part is in the blood. To reach 

 all of these places it is necessary to make injections into the 

 vein and under the skin as well. The surgeon attempts to 

 reach those parts first which have been affected the longest, 

 to halt at once any further damage there, and therefore 

 methods of treatment vary. Antitoxin is sometimes injected 

 directly into the nerves in order that some may neutralize 

 what toxin is remaining in them along their length or in their 

 muscle distribution. In severe, rapidly developing cases it 

 may be injected into the meningeal space or directly into the 

 brain tissue. 



It is best to give 10,000 units by the vein and repeat 

 at several-hour intervals until symptoms start to abate. 

 The sooner after the symptoms appear that antitoxin is 

 given the more favorable is the outlook. Antitoxin is now 

 given freely by health authorities, to all who receive firearm 



