TETANUS ANTITOXIN 547 



inoculated in such a way as to suffer from an attack of the disease which rapidly 

 runs its course the serum will in most cases be ineffective. It may succeed in slowly 

 developing infections but in these cases again the prevention of the disease is not 

 always certain unless the site of infection be excised. The disease may appear to 

 be checked but it is liable to break out again and terminate fatally even after a 

 considerable lapse of time." 



The cure of the disease after the symptoms have manifested themselves is 

 therefore always difficult because the appearance of the symptoms is itself 

 evidence that the nerve elements are already involved. Antitoxin neutralizes 

 toxin circulating in the body but is totally ineffective against existing lesions. 

 Very large doses of the more powerful serums are without effect on a rapid 

 case of tetanus : such doses render the blood antitoxic and immunizing but the 

 disease pursues its course. In less severe cases the serum prolongs life but 

 unless the focus of infection be removed the disease will develop so soon as 

 the antitoxic power of the blood shall begin to diminish. 



In man also, the serum therapy of tetanus has yielded but indifferent 

 results. The treatment fails in the more severe forms of the disease. It 

 only seems to give positive results in sub-acute or chronic cases, and it is 

 well known that these cases when treated by the ordinary methods often 

 terminate in recovery. However that may be, the serum treatment of 

 tetanus is harmless and should be adopted in all cases of the disease in man. 



Roux and Vaillard define the course of treatment in cases of tetanus in man as 

 follows : 



" Inoculate at once, and without waiting, 100 c.c. of a very powerful serum, and if 

 possible excise the infected area. Another 100 c.c. should be administered on the 

 following day and on the day after that. If the symptoms are checked, and especi- 

 ally if the focus of infection has not been excised, give a further dose of serum ten 

 days later to obviate any recurrence of the disease such as has been described as 

 taking place in animals." 



In view of the failure of treatment, attention has been directed to the pre- 

 vention of the disease in man and animals. Whenever a contused wound 

 soiled with earth has to be treated it is well to inoculate, as a precautionary 

 measure, 20-30 c.c. of antitetanus serum and the inoculations should be 

 repeated in doses of 10-15 c.c. every week until all danger of tetanus has 

 vanished. Nocard, in veterinary practice, has obtained very good results 

 with prophylactic inoculations in cases of wounds of the foot and after 

 castration. 



Calmette has shown that animals can easily be immunized against tetanus by 

 sprinkling a small wound involving the whole thickness of the dermis with dry 

 powdered serum (vide ante). As a prophylactic measure, he advises the use of dried 

 serum for dressing wounds liable to be infected with tetanus and especially in those 

 countries where the disease is rife. 



Intra-cerebral inoculation. These facts render it difficult to understand 

 how tetanus toxaemia continues to develop in animals which have been 

 treated with antitoxin and whose blood is prophylactic and antitoxic. The 

 researches of Roux and Borrel have thrown some light on the mode of action of 

 antitoxin and have given a new impetus to the serum treatment of the disease. 



A neutral mixture of toxin and antitoxin is harmless to the nerve cells. It 

 can be inoculated into the brain of a rabbit without any untoward incident 

 occurring. Again, a rabbit immunized with serum, while unaffected by the 

 sub-cutaneous inoculation of a quantity of toxin which is five times the lethal 

 dose for an untreated animal, will nevertheless die if O'l c.c. of toxin be 

 inoculated into the brain. 1 However, its blood is so antitoxic that a few 



1 This quantity when inoculated sub-cutaneously is absolutely without any effect on a 

 normal rabbit. 



