2o8 MANUAL OF BACTERIOLOGY. 



In all cases where a human being has been bitten by a dog 

 that is suspected of having hydrophobia, the individual should 

 submit himself to the Pasteur treatment as soon as possible, 

 if it is feasible to do so. Since this treatment, if done by com- 

 petent hands, insures the person who has been bitten against 

 the danger of the development of the disease. 



In order to find out whether the dog has hydrophobia, the 

 animal may either be put up and observed to see whether char- 

 acteristic symptoms develop, or it may be immediately killed. 

 In the latter case the brain and cord should be examined for 

 the presence of the Negri bodies already alluded to, and the 

 intervertebral ganglia for the presence of round-cell infiltration 

 which is often marked. Rabbits or guinea-pigs should also be 

 inoculated under the dura. As stated in the beginning, it is 

 safer not to wait for the result of the examination, but to sub- 

 ject the person, who is bitten, to the Pasteur treatment in 

 advance of this, unless it is improbable that the dog is mad. 

 The examination consists in looking for the Negri bodies and 

 in subdural inoculation of rabbits. If the cord of the dog can 

 be obtained, the intervertebral ganglia will show round-cell 

 infiltration. All other ganglia may also show this change. 

 The plexiform and Gasserian ganglia are convenient for 

 examination. 



Great care must be taken that the operator may not acciden- 

 lally infect himself. 



Antitoxins. — Antitoxins have as yet been produced for the 

 extra-cellular toxins only, and only those diseases which are 

 caused by bacteria which form extra-cellular toxins have been 

 successfully combated in this way. Antiendotoxins, on the 

 other hand, have not yet been satisfactorily produced. Buxton* 

 found that rabbits immunized with typhoid bacilli do not 

 become appreciably more resistant than normal rabbits to 

 the endotoxin of the typhoid bacilli. 



* Journ. Med. Research. V. XVI., No. 2, May, 1907. p. 264. 



