VACCINES IN TREATMENT OF DISEASE 251 



creasing doses than by a single injection of a 

 large dose. At the same time, the clinical effects 

 in the individual case must be made the basis 

 for the size and frequency of the doses ; for the 

 dosage is influenced by the nature of the in- 

 fection, and also by the individual susceptibility. 

 Should no improvement be noted, and the clini- 

 cal reaction permits, the size of the dose may be 

 increased or the intervals shortened, or both. 

 If a pronounced clinical reaction occurs char- 

 acterized by fever and aggravation of local 

 symptoms it indicates that the dose has been 

 too large, and the next injection should be 

 smaller. 



The amount of vaccine required varies ac- 

 cording to the age and personal characteristics 

 of the patient; and the type, duration, extent 

 and severity of the infection. It is important 

 to bear in mind, however, that the packages con- 

 taining four or six different dilutions, as 

 marketed by most laboratories, do not in any 

 sense constitute a complete treatment. It is 

 impossible to prepare any four or six gradu- 

 ated doses which will meet the conditions of 

 every case ; some cases might require fifteen or 

 more doses, while four might suffice for others. 



