SMALL-POX VACCINATION. 83 



cians outside of the City of New York. In such cases a stronger 

 course of treatment is followed and an effort is made to limit this 

 practice to places not more than twenty-four to thirty-six hours' 

 distance from the laboratory. 



The results of Pasteur treatment or active immunization 

 against hydrophobia are most satisfactory. Without specific treat- 

 ment the mortality in patients bitten by rabid dogs varies from 50 

 to 80 per cent, while in patients who have undergone a course of 

 active immunization the death rate is about 0.5 per cent. To get 

 good results, early treatment is essential, Bites on the face and 

 head, and bites by mad wolves are not immunized against as suc- 

 cessfully as bites by dogs in other parts of the body. After the 

 symptoms of the disease have developed, active immunization can 

 no longer be expected to be of value. 



Immunization against rabies has also been attempted by the 

 injection of anti-rabic serum. Babes and Lepp in 1889 found that 

 they could protect dogs against rabies by injection of serum from 

 dogs actively immunized to rabies. Tizzoni and Centanni have 

 reported favorable results with anti-rabic serum. Marie has re- 

 cently advocated the simultaneous injection of virus and anti-rabic 

 serum. By this method it is possible to immunize against hydro- 

 phobia more rapidly. The value of these newer methods has not 

 been proven so that at the present time conclusions as to their 

 value are impossible. 



Small-pox. Small-pox is a disease for which the etiological 

 factor- has not been determined, although Guanieri, Councilman, 

 Calkins and others have found protozoan parasites in the lesions 

 of the disease. 



For a long time it has been known that one attack of small- 

 pox will protect against subsequent contraction of the disease. 

 This has led to the practice of acquiring immunity against severe 

 forms of the disease by intentional inoculation and contraction of 

 mild forms of the disease. 



In 1796, Jenner inoculated a boy with virus from cow-pox on 

 a dairy-maid's hand, and found that in this way cow r -pox can be 

 transmitted and immunity to small-pox be produced. Since then 

 vaccination against small-pox by inoculation of cow-pox has been 

 quite universally adopted. It is now accepted that cow-pox is a 

 modified form of small-pox and that small -pox vaccination is a 



