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APPLIED BACTERIOLOGY 



Antirabic Serum. — Valli, an Italian physician, early in the 

 present century, showed that by administration through the 

 stomach of progressive doses of hydrophobic virus, animals 

 could be rendered immune against rabies. This important 

 observation seemed to be lost sight of till Tizzoni and 

 Centanni investigated this discovery. They also succeeded 

 in immunising animals by the gradually increasing injec- 

 tion of rabic virus which they had attenuated by submitting 

 it to peptic digestion. They furthermore found that the 

 blood-serum of animals so immunised conferred passive 

 immunity in other animals, and if injected into animals 

 not more than fourteen days after infection, it prevented 

 fatal effects, even if symptoms had already shown them- 

 selves. The serum would appear to contain similar anti- 

 toxic bodies such as are produced in the case of other 

 diseases. 



Owing to the want of statistical information in the case 

 of persons bitten by really rabid dogs, it is impossible to 

 form a true idea of the value of Pasteur's treatment, seeing 

 we do not know the percentage of cases in which hydro- 

 phobia follows the bite of a rabid dog, and that in the 

 majority of cases reported the animal was not rabid at all. 



