548 THE TETANUS BACILLUS 



drops neutralize considerable quantities of toxin. And further, a trace of 

 the blood accidentally spilt in the path of the inoculating needle as it 

 traverses the brain is sufficient to neutralize the toxin and the animal does 

 not die. 



Antitoxin given sub-cutaneously or intra-venously remains in the blood. 

 It has no affinity for the nerve elements. These latter, on the other hand, 

 pick out and fix the toxin (vide ante). In an animal suffering from tetanus 

 the antitoxin given sub-cutaneously or intra-venously limits the poisoning 

 by destroying the toxin circulating in the blood but it does not come in 

 contact with the toxin already fixed by the nerve elements, which diffuses 

 from cell to cell and so extends its ravages. Antitoxin should, therefore, 

 not be inoculated into the blood of those suffering from the disease but rather 

 into the nerve centres. Proof of the correctness of these views is afforded 

 by the results of direct inoculation of antitoxin into the brain. 1 Roux and 

 Borrel took a number of guinea-pigs and inoculated them sub-cutaneously 

 with a lethal dose of toxin. Twenty-four hours later these animals showed 

 symptoms of tetanus. Some of them were then inoculated with 1 c.c. of 

 serum sub-cutaneously and in spite of this they died. The remainder were 

 treated with 4 drops of the same serum in each cerebral hemisphere with the 

 result that the disease was arrested and the animals recovered, though some 

 of them suffered from localized spasms for a long time. In these cases the 

 inoculation preserved the upper parts of the cord against the diffusion of the 

 toxin but was without effect on the lesions already present in the lower parts ; 

 hence the persistence of the spasms present at the time of the therapeutic 

 inoculation. Similar experiments showed that when the upper part of the 

 cord is affected the inoculation is too late and fails to save the life of the 

 animal. 



The cure of human tetanus would seem to follow from these investigations. 

 Unfortunately, in practice, the results are very inconstant. Against the 

 rare cases of recovery following intra-cerebral inoculation of antitoxin recorded 

 by Lucas-Championniere, Girard, Chauffard, Nimier, Ledoux, Maunoury, 

 Holub and others have to be recorded the numerous failures and even rapidly 

 fatal accidents reported by other observers (Vallas, Girard, Tailhefer and 

 others). 



5. Agglutination. 



The serum of normal persons does not agglutinate the tetanus bacillus. 

 In cases of tetanus in man, the blood does not acquire agglutinating properties 

 (Courmont). The same is true of laboratory animals. 



Normal horse serum agglutinates the tetanus bacillus feebly (1 in 50 to 

 1 in 100). The serum of an highly immunized horse agglutinates the bacillus 

 in dilutions of 1 in 2,000 and even in 1 in 50,000. 



The inoculation of antitetanus serum only confers an agglutinating pro- 

 perty when given in considerable doses (Courmont). 



SECTION IV. DETECTION AND ISOLATION OF THE TETANUS 



BACILLUS. 



When it is desired to isolate the bacillus from or to detect its presence in 

 soil, a small quantity should be inoculated into a guinea-pig ; the bacillus 

 if present can be easily demonstrated in and isolated from the tissues after 

 death. 



1 Inoculation of antitoxin into the spinal cord is difficult to effect without producing 

 lesions and moreover does not appear to be as efficient as intra-cerebral inoculation. 

 Sub-arachnoid inoculation does not give satisfactory results. 



