200 ACTIVE IMMUNIZATION 



to the extent of 0.5 per cent., and allowed to stand for twenty-four 

 hours before being used. 



During epidemics Shiga recommends that still larger doses of 

 the vaccine be used, or to vaccinate three times with increasing 

 quantities. 



DYSENTERY 



Protective vaccination against bacillary dysentery has likewise 

 been attempted, but has not as yet led to results which are compar- 

 able in value to what we see in the case of plague and cholera. Shiga 

 himself inoculated some 10,000 individuals between 1898 and 1900, 

 and thought that he could note a decrease in the mortality, while 

 the morbidity and the severity of the symptoms were apparently 

 uninfluenced. The dead cultures, however, are so highly toxic 

 that this element in itself is an obstacle to the more general use of 

 such a vaccine. Whether further investigations in this direction 

 will lead to more practical results time only can tell, but it would not 

 seem to be out of the question, particularly when coupled with the 

 use of a corresponding antitoxic serum. 



OTHER DISEASES 



In the other infectious maladies to which the human being is 

 subject protective vaccination has either not yet been attempted or 

 has not yielded encouraging results. There are a number of infec- 

 tious diseases, however, occurring in the domesticated animals 

 against which vaccination may be successfully employed. This is 

 notably the case with anthrax, swine plague (Schweinerotlauf), 

 cattle plague (Rinderpest), sympathetic anthrax (Rauschbrand), 

 and within certain limitations also with cattle tuberculosis. For a 

 consideration of the methods employed and the results which have 

 been reached in these diseases which so closely affect the human 

 being the reader is referred to special works. 



(B) ACTIVE IMMUNIZATION FOR THERAPEUTIC PURPOSES 



While in the diseases which have thus far been considered, active 

 immunization will only furnish results of value when carried out for 

 prophylactic purposes, whereas the same measures have no influence, 



