RESISTANCE OF THE BODY 



95 



Vaccination or Jenner's process is still the recog- 

 nized preventive or protective measure, and it has re- 

 duced small pox from a dread pestilence to a disease 

 producing fewer deaths than measles. 



The great Pasteur reasoned that "if an infectious 

 disease be really a struggle for supremacy between 

 man and microbe, it is probable that in vaccination for 

 small pox the struggle is less severe for the patient, 

 because the germs of small pox have somehow been 

 weakened or enfeebled by their residence in the cow." 



The use of antitoxine for the prevention or treat- 

 ment of diphtheria is perhaps the best example of that 

 method of producing immunity. In this case the horse 

 is chosen as the intermediate host for the production 

 of antitoxine material. The toxines, or sometimes 

 the germs themselves, are injected into the body of 

 the healthy animal. The first dose is usually a small 

 one. A slight reaction or fever may be noticed. The 

 doses are gradually increased until the animal is found 

 to be immune. Blood is then drawn from this immune 

 horse and "its serum is found to contain the anti- 

 toxine in abundance." 



Some of this serum is then injected into a per- 

 son who has been exposed to, is likely to be, or is 

 ill with the disease. In the last case, to be effective, 

 the antitoxine must be introduced at an early stage of 

 the disease when there is not too much toxine to be 

 neutralized. 



By the use of antitoxine thus obtained, the mortality 



Making 

 Antitoxine 



Diphtheria 



Antitoxine 



