MKTHODS 5S3 



ellicacy of the treatment, but again attention may be directed to 

 the bearing which the development of hypersensitiveness may 

 have to the occurrence of the phenomena of infective disease, 

 and Harvey and McKendrick draw attention to the fact that 

 some of the concurrent symptoms associated with the treatment 

 closely resemble anapliylactic phenomena. 



J /////'//,/ .s'r rum. In the early part of the nineteenth century 

 an Italian physician, Valli, showed that immunity against rabies 

 could In- conferred by administering through the stomach pro- 

 gressively increasing doses of hydrophobic virus. Following up 

 this observation, Tizzoni and Centanni have attenuated rabic 

 virus by submitting it to peptic digestion, and have immunised 

 animals by injecting gradually 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 

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

 animals from seven to fourteen days after infection with the 

 virus, it prevented the latter from producing its fatal effects, 

 even when symptoms had begun to manifest themselves. They 

 fiirthur succeeded in producing in the sheep and the dog an 

 immunity equal to from 1-25,000 to 1-50,000 (vide p. 525), and 

 they recommended the use, in severe cases, of the serum of such 

 animals in addition to the treatment of the patient by the 

 Pasteur method. A like serum has been obtained from animals 

 treated by the ordinary Pasteur method. 



Methods. (1) Diagnosis. Recent work with regard to the 

 specificity of the Negri bodies for rabies has led to a modifica- 

 tion in the procedure to be adopted. Formerly it was advisable 

 if possible to keep an animal suspected of rabies alive for the 

 observation of symptoms. While the clinical history of the 

 animal ought to be carefully obtained, greater information will 

 be obtained by examination of its hippocampus. The animal 

 should therefore le killed and the brain removed after reflecting 

 the scalp and cutting through the calvarium with a sharp chisel. 

 The brain is laid down, vertex uppermost, and the upper parts 

 of one hemisphere are removed in thin horizontal slices till the 

 anterior part of the lateral ventricle is reached. The roof of the 

 ventricle is then cut away with a probe-pointed bistoury, and 

 the hippocampus will be recognised as the laterally arched ridge 

 which forms the floor of the ventricle. This may be transversely 

 incised and parts removed for the making of smears and sections 

 (p. r,76). ^ 



In addition to microscopic examination, a small piece of the 



