VACCINES IN PROPHYLAXIS OF DISEASE 199 



jection should be made in a widely distant area 

 of tissue, and with a freshly sterilized syringe 

 and needle, using vaccine in vial next in order 

 numerically. No after-treatment of the site of 

 injection is required. 



Prognosis The outlook is most favorably in- 

 fluenced by the Pasteur treatment. At the Paris 

 Institute, up to January, 1904, there had been 

 treated 17,719 cases of all descriptions with 117 

 deaths, making a mortality of 0.42 per cent. As 

 in other methods of vaccination, immunity is 

 produced only after a certain lapse of time ; and, 

 in cases of short incubation or of late com- 

 mencement of the treatment, the disease may 

 manifest itself before the effect of vaccine has 

 been procured. The work of Krauss and Kreis- 

 sel throws much light on the production of im- 

 munity by the Pasteur treatment and empha- 

 sizes the importance of beginning treatment 

 promptly. These authors find that the serum of 

 healthy individuals as a rule does not contain 

 any protective property against the virus of 

 rabies, nor is any found immediately after the 

 completion of antirabic treatment; but twenty- 

 two days later, marked antirabic power is pres- 

 ent and is retained for a long time. 



