﻿426 STRONG. 



Karwacki 22 inoculated nine persons with about 1 oese of killed cholera 

 organisms suspended in saline solution. After five days a second dose of 2 oesen 

 was injected, following which, apparently quite marked local reaction occurred. 

 The reactions were usually milder after the second than after the first injection. 

 After the first vaccination the bactericidal value of the serum was 0.02 in eight 

 of the cases (50 units) ; after the second the sera showed values of from 2,000 

 to 10,000 units. The agglutination after the first inoculation in no ease reached 

 over 1 : 50. In some instances there was no reaction in dilutions of 1:5, while 

 after the second vaccination the agglutination was in no ease below 1 : 5 and in 

 one it had reached 1 : 400. 



Blell a ( from the Institute for the Investigation of Infectious Diseases in 

 Bern) has also reported in detail upon the value of cholera immunization with 

 cholera nucleo-proteid. The agglutinative and bactericidal value of the blood 

 sera of a large number of animals was studied. Many of these had received 

 repeated and increasing doses of the prophylactic. In two cases the bactericidal 

 value of the rabbit's blood was determined after single injections of 0.1 gram 

 and 0.05 gram, respectively, of the nucleo-proteid and was found to be 5 milli- 

 grams and 10 milligrams. In the rabbits which had received a number of 

 repeated inoculations, sera to a maximum value of 0.8 of a milligram were 

 obtained. 



The author also reports experiments from the results of which he believes that 

 cholera immune serum produced by inoculation of the nucleo-proteid may exert 

 a curative effect on animals which are inoculated with it in from one to four 

 hours after infection with living cholera spirilla. 



Finally, we have the report of Haffkine 2i which gives a summary of the work 

 performed on anti-cholera inoculation in India. Haffkine refers to the recent 

 work of Pfeiffer and Friedberger and of myself, which seemed to demonstrate that 

 the vaccinating power of a cholera culture varies in direct relation with the 

 degree of its virulence, a principle he remarks which served Pasteur for twenty 

 years as a basis for his "traitement intensif" in rabies. Haffkine points out that 

 for this reason in the beginning of his work on protective inoculation against 

 cholera he sought to obtain a "virus fixe" with the cholera vibrio. 



In his very extensive inoculations in man he has observed that the intensity 

 and duration of the symptoms provoked by the subcutaneous inoculation of the 

 living vibrios are directly proportional to the virulence of the culture and the 

 quantity injected. He again describes the methods by means of which the fixed 

 and the attenuated virus used in making the inoculations are prepared. He has 

 found that if the cultures of the organism are killed by heat or by antiseptics 

 such as carbolic or inorganic acids, or by other means, they retain the power of 

 producing an immunity upon inoculation, but this is considerably reduced. The 

 reaction produced after injection of the killed cultures was of the same nature 

 as that brought about by the living ones, only it was less intense. Up to the year 

 1895 Haffkine always employed two vaccines, the first consisting of a culture 

 attenuated by growing it in contact with the oxygen of the air, and the second, 

 a virus of fixed virulence obtained by passage through guinea pigs. Since 1895, 

 owing to the fact that it was found impracticable sometimes to give the second 

 inoculation, experiments were made by Haffkine and Powell to see if the first 

 vaccination with the attenuated culture could not be omitted. As much as A 

 of a gelatin culture of the fixed virus alone was injected in a large number of 



^Ztschr. f- Syg. u. Infektionskrankh., Leipz. (1906), 54, 39. 

 23 Ztschr. f. Hyg. u. Infektionskrankh., Leipz. (1906), 55, 187. 

 "Bull. Inst. Pasteur (1906), 4, 694 and 737. 



