ANT1RABIC SERUM. 473 



into three classes. Class A includes only persons bitten by 

 dogs proved to have had rabies, by inoculation in healthy 

 animals of parts of their central nervous system. Class B 

 includes those bitten by dogs that a competent veterinary 

 surgeon has pronounced to be mad. Class C includes all 

 other cases. During 1895, 122 cases belonging to Class A 

 were treated, with no deaths; 949 belonging to Class B, 

 with two deaths ; and 449 belonging to Class C, with no 

 deaths. Besides the Institute in Paris, similar institutions 

 exist in other parts of France, in Italy, and especially in 

 Russia, as well as in other parts of the world ; and in these 

 similar success has been experienced. It may be now 

 taken as established, that a very grave responsibility rests 

 on those concerned, if a person bitten by a mad animal is 

 not subjected to the Pasteur treatment. Two practical 

 points in dealing with such a case are to be noted : (i) the 

 wounds ought to be cauterised with the actual cautery as 

 soon as possible ; and (2) if the person is sent to a Pasteur 

 institute, the head of the animal which inflicted the bite 

 ought also to be sent packed in ice, in order that by 

 inoculation its madness may be definitely ascertained. 



Antirabic Serum. In the early part of the present 

 century an Italian physician, Valli, showed that immunity 

 against rabies could be conferred by administering through 

 the stomach progressively increasing doses of hydrophobic 

 virus. Following up this observation, Tizzoni and Cen- 

 tanni have attenuated rabic virus by submitting it to peptic 

 digestion, and have immunised animals by injecting gradu- 

 ally increasing strengths of such virus. This method is 

 usually referred to as the Italian method of immunisation. 

 The latter workers showed from this that the serum of 

 animals thus immunised could give rise to passive im- 

 munity in other animals ; and further, that if injected into 

 animals from 7 to 14 days after infection with the virus, 

 it prevented the latter from producing its fatal effects, even 

 when symptoms had begun to manifest themselves. They 

 further succeeded in producing in the sheep and the dog 

 an immunity equal to from 1-25,000 to 1-50,000 (vide 



