148 CLINICAL BACTERIOLOGY AND 



negative phase, it will go higher at this period, and it is 

 then the danger of a dose too large for Nature to assimilate, 

 so to speak, comes in. This is a principle applicable to all 

 acute diseases, as has already been pointed out, so far as 

 vaccine-therapy goes. 



Strangles. 



This disease is very prevalent in young horses at certain 

 seasons of the year, and in some years more so than in 

 others. It is a specific infective fever, and when running 

 a simple course it affects the upper air-passages and in- 

 vades the neighbouring local lymphatic system. 



The streptococcus which is responsible for this condition 

 is found in the nasal organs, and possibly exists as a non- 

 pathogenic bacterium in many instances. The disease may 

 run a very mild course, and pass off only as a simple 

 catarrh. This may be due to the low virulence of the 

 bacteria themselves, or the increased resisting powers of the 

 antibodies of the blood itself, or both. 



In an ordinary simple case of strangles special treatment 

 is not called for, and all that is necessary is to keep the 

 patient from contracting chills. Complications are, how- 

 ever, liable to supervene, in which case they must be 

 treated upon their merits. 



If the disease runs an irregular course, the immunizer 

 can do much to fortify his patient and prevent septicaemic 

 or metastatic lesions developing by the injection of an 

 autogenous vaccine. 



Here, too, if the disease is one of considerable standing, 

 a mixed infection has to be looked for ; in which case the 

 causative bacteria must be identified, and suitable vaccines 

 made. 



When Ave have under treatment a bad case, which 

 does not seem to respond to vaccine treatment, we make 

 it a practice of combining the vaccine with antistrepto- 

 coccic serum. 



