VACCINES IN TREATMENT OF DISEASE 239 



disease and thus aid the infected tissue-cells in 

 overcoming the infection. 



We desire to emphasize the following points 

 in vaccine therapy: (1) Every case must be 

 individually studied just as when administer- 

 ing drugs and the size, number and frequency 

 of doses must be adapted to the needs of the 

 individual case. (2) The necessary medical and 

 surgical measures must not be neglected, for 

 reliance should not be placed solely on the ac- 

 tion of the vaccine. (3) Vaccines have failed 

 in many instances to give the desired results 

 because they were given in cases unsuited to 

 vaccine therapy. (4) Vaccines must not be ex- 

 pected to construct tissues that have been de- 

 stroyed by pathogenic bacteria. (5) To be ef- 

 fective, vaccines must be timely and intelli- 

 gently administered. 



Negative Phase When Wright announced 

 his theory of the negative phase and the in- 

 creased risk to infection during the period of 

 this phase, progress in vaccine therapy for a 

 time was checked. Accumulative practical ex- 

 perience of Sir William B. Leishmann of the 

 English Army, however, enabled him to refute 

 this theory most emphatically, and to prove con- 



