SCIENCE IN MEDICINE 243 



tetanus antitoxins are examples, possess the power of neutral- 

 ising poisons, and have met with great success in the treatment 

 of diphtheria, and with some success in that of tetanus ; further, 

 both are standardised so as to enable the physician to regulate 

 the dose at will. 



The anti-bacterial sera, on the other hand, in spite of an 

 extended trial, have practically met with no success ; the cause 

 of this must now be inquired into. Wright, 1 in a paper read 

 before the Chelsea Clinical Society, explains their failure in 

 this way. In anti-bacterial serum-therapy the physician pro- 

 poses to administer to the patient protective substances ela- 

 borated in the organism of an animal which has been vicariously 

 inoculated with the appropriate bacterial vaccine. If the serum 

 used is to be of benefit to the patient it is essential that it should 

 contain a certain quantum of anti-bacterial substances. As we 

 saw in the case of the anti-diphtheria and anti-tetanus sera the 

 antitoxic value is measured, and they have been found to contain 

 a large number of anti-bodies. But in the case of other sera 

 no such examination is instituted, and in consequence it is not 

 known whether these preparations have any anti-bacterial pro- 

 perties at all. It is assumed in their manufacture that the 

 animal which is being inoculated will respond to each inoculation 

 by the elaboration of more anti-bacterial substances. This 

 assumption is based on analogy with the manufacture of the 

 anti-diphtheritic and anti-tetanic sera, but that this is not 

 justified is proved by the fact that every animal inoculated 

 against the diphtheria bacillus does not elaborate anti-bodies; 

 some only do so to a limited degree, and some die during the 

 inoculations. It is therelore essential that all sera should be 

 subjected to a searching examination ; the proper course for 

 the bacteriologist is " to verify everything, to measure every- 

 thing, and to declare in each case the results of his measurement." 

 After the inoculation of a bacterial vaccine into an animal the 

 immediate effect is a lowering of the resistance of the blood, 

 and this is followed by an increase in resistance above the 

 normal. If this animal is bled when it has completely recovered 

 from the effects of the inoculation, it is probable that its serum 

 contains a certain quantum of anti-bacterial substances — but it 

 is inexcusable to assume that this is so without measurement ; 

 for even if, in response to the infection, the elaboration of pro- 



1 Clin. Journ., May 16, 1906. 



