224 PASSIVE IMMUNIZATION 



As the blood of adults, moreover, has been found to contain not 

 inconsiderable amounts of natural diphtheria antitoxin, the use of 

 horse antitoxin is less urgent in these for prophylactic purposes than 

 in children and can indeed often be neglected. 



Results. If now we come to study the effect which the treat- 

 ment of diphtheria with antitoxin has had upon the mortality of the 

 disease, it is apparent from a survey of the accompanying table that 

 the lowest death rate will be obtained, if the injections can be given 

 on the first day, and that the mortality percentage increases for 

 every day that the treatment is delayed. Taking the results corre- 

 sponding to the first day we have an average of 4.8 per cent. Further 

 argument than this should be unnecessary to convince anyone 

 that in the use of antitoxin we now have a weapon in the face of 

 which diphtheria has indeed lost its terrors, and that a physician 

 who refuses to avail himself of its use is indeed unfitted to practise his 

 profession. 



Later 



No. of Mortality First Second Third Fourth Fifth Sixth than 

 Author. cases, per cent. day. day. day. day. day. day. sixth. 



Welch . . . . 1489 14.2 2.3 8.1 13.5 19.0 29.3 34.1 33.7 

 Hilbert .... 2428 18.3 2.2 7.6 17.1 23.8 33.9 34.1 38.2 

 Collective report of 



American Pedia- 



tric Society . . 5794 12.3 4.9 7.4 8.8 20.7 35.3 

 Austrian collective 



report . . . 1103 12.6 8.0 6.6 9.8 25.5 28.8 30.7 21.0 

 German collective 



report ... 9581* 15.5 6.6 8.3 12.9 17.0 23.2 ... 26.9 



In the earlier days of the use of antitoxin the question was asked 

 whether the lower mortality could not be explained on the assump- 

 tion that the diphtheria epidemic which was then prevailing was of 

 an unusually mild type. We know as a matter of fact that the 

 "virulence" of a disease undergoes periodical fluctuations, so that 

 there is some reason in such a suggestion. But even so, the low 

 mortality, when treatment was instituted on the first day, which was 

 early noted, should have been sufficient to dispose of this possibility, 

 for up to that time no treatment that had been previously in use 

 could boast of such a result. But aside from this there are many 

 other observations which prove beyond a shadow of a doubt that the 

 low general mortality from diphtheria is really due to the use of 

 antitoxin and not to accidental factors. At the Blegdam Hospital 



