ANTIRABIC VACCINATION 63 



ployed. This is known as the " intensive " treatment. 

 It is necessary to employ this latter method when 

 wounds occur in the region of the head, on account 

 of the shorter period of incubation in these cases. 

 In the " intensive " treatment, cords dried for three 

 or four days should be employed on the seventh day, 

 instead of the ninth or tenth day, as in the ordinary 

 treatment. 



The technique of this vaccination varies in 

 different countries. Thus, the Italian method of 

 Tizzoni and Centanni is to treat the spinal cord with 

 gastric juice, which has an attenuating effect on the 

 virus. 



Hogyes, in Buda-Pest, merely dilutes an emulsion 

 of virulent material to different degrees, using a high 

 dilution for the first injection, and gradually raising 

 the concentration on succeeding days. The theory 

 underlying this procedure is that the usual method of 

 attenuation by drying alters the quantity but not the 

 quality of the virus ; in other words, it kills a certain 

 proportion of the poisons, so that a smaller number 

 of them are injected at a dose, but it does not alter 

 their virulence. Hence the same results may be 

 attained by simple dilution. By this last method a 

 vaccine can be prepared much quicker than by the 

 original method of Pasteur. 



Site of Injection. — The immunising injections can 

 be made subcutaneously in the neck in horses, and in 

 dogs in the region of the abdomen ; it is necessary to 



