DIPHTHERIA ANTITOXIN 425 



The Indian Plague Commission concluded that (1) inoculation 

 sensibly diminishes the incidence of plague attacks on the inoculated 

 population, but the protection afforded is not absolute ; (2) inocula- 

 tion diminishes the death-rate among the inoculated population ; (3) 

 inoculation does not appear to establish protection until after some 

 days ; and (4) protection is conferred for a considerable number of 

 weeks and possibly for months. Finally, the Commission recom- 

 mend that under the safeguards and conditions of accurate 

 standardisation and complete sterilisation of the vaccine, and the 

 thorough sterilisation of the syringe in every case, inoculation should 

 be encouraged wherever possible, and in particular among disinfecting 

 stuffs, and the attendants of plague hospitals. 



Antitoxin Inoculation foF Diphtheria 



We may now consider an illustration of passive immunity. This, 

 it will be remembered, may be defined as a protection (against a 

 bacterial disease) produced by inoculation, not of the disease itself, 

 as in small-pox inoculation, nor yet of its weakened toxins, as in 

 rabies, but of the antitoxins produced in the body of an animal 

 suffering from that particular disease. Examples of this treatment 

 are increasing every year. The chief examples are to be found in 

 Diphtheria, Tetanus, Streptococcus, and Pneumococcus. 



To be of value, antitoxins must be used as early as possible, 

 before tissue change has occurred and before the toxins have, so to 

 speak, got the upper hand. When the toxins are in the ascendency 

 the patient suffers more and more acutely, and may succumb before 

 there has been time for the formation in his own body of the neutral 

 compound of toxin and antitoxin. If he can be tided over the 

 "crisis," theoretically all will be well, because then his own anti- 

 toxin will eventually gain the upper hand. But in the meantime, 

 before that condition of affairs, the only way is to inject antitoxins 

 prepared in some animal's tissues whose disease began at an earlier 

 date, and thus add antitoxins to the blood of the patient, early in the 

 disease, and the earlier the better, for, however soon this is done, it 

 is obvious that the toxins begin their work earlier still. It should 

 not be necessary to add that general treatment must also be con- 

 tinued, and indeed local germicidal treatment, e.g. of the throat in 

 diphtheria and the poisoned wound in tetanus. Further, in a mixed 

 infection, as in glandular abscesses with diphtheria, it must be borne 

 in mind that the antitoxin is specific, and may therefore probably 

 fail to reduce the complication which must be treated separately. 



In the production of antitoxins, an animal is required^ from 

 whose body a considerable quantity of blood can be drawn without 

 injurious effect. Moreover, it must be an animal that can stand 



