144 CLINICAL BACTERIOLOGY AND 



When one is dealing with a mixed inf ection, it is obvious, 

 if vaccine-therapy is to serve its intended purpose, a 

 vaccine of all the causative bacteria must be obtained. In 

 practice it is difficult to estimate to each bacterium the 

 degree of pathogenicity which that particular bacterium 

 has the power of exercising, and it is probable that in each 

 individual case the degree varies considerably in the same 

 species of bacteria at different times and in the same 

 case. 



To ascertain the nature of infection, one must collect the 

 pathological material at one's disposal. In animals we 

 obtain such from the nasal discharges, and the materis 

 morbi should be carefully collected, to prevent outside con- 

 tamination, as already described. 



If the patient has had a good previous health record, we 

 begin by giving the following doses, assuming, of course, 

 all these bacteria are present : 



Staphylococci 500,000,000 



Streptococci 100,000,000 



Diplococci 500,000,000 



Micrococcus catarrhalis . . . 250,000,000 



The clinical phenomena should be carefully noted. 



Some twelve hours after injection the temperature will 

 usually rise one or two degrees, the pulse-beat will be 

 increased in number 10 to 20 per minute, and the respiration 

 increases 5 to 15 per minute. 



The cough is usually more irritable and the catarrhal 

 discharge increased in quantity, but more tenacious in 

 consistence. On the whole, there is a proportionate general 

 depression. To sum up, these phenomena constitute the 

 negative phase, which are salutary if the vaccine has 

 responded in the manner one desires, and they are to be 

 expected if one anticipates good results to follow. If no 

 such characteristics are noticed, the dose is too small or 

 there is some error in the technique, and a close investiga- 

 tion is called for. 



