﻿REPORT ON CHOLERA IN MANILA. 423 



REVIEW OE THE RECENT WORK UPON PROTECTIVE INOCULATIONS AGAINST 



CHOLERA. 



Having briefly outlined the work carried on in this laboratory in 

 connection with prophylaxis against cholera, T wish to review the results 

 which several other observers have obtained with different methods of 

 anti-cholera inocidation, since the publication of my last article upon 

 the subject. 12 



Bertarelli ,s in April, 1905, performed a few experiments in cholera immuniza- 

 tion, using for the injections the receptors of the spirillum separated by autolysis, 

 but the strength of the autolytie product employed is not given. He inoculated 

 himself subcutaneously with 3.6 cubic centimeters and a rabbit with 5 cubic 

 centimeters of such a prophylactic and was able for more than six months after 

 the inoculation to demonstrate agglutinative and bactericidal substances in the 

 blood in each instance. During the previous year, I had already shown that in 

 the blood these antibodies persisted for a longer period of time than six months 

 after inoculation with the immunizing substances extracted by autolysis from 

 the organism. Bertarelli's experiments do not appear to be sufficiently extensive 

 to throw much light upon the value of the method of immunization with the 

 autolytie extracts of the cholera organism, although he apparently considers this 

 method of inoculation of value. 



Heller, 14 (Sehweizer Serum und Impfinstitut, Bern), after pointing out the 

 advantages of protective inoculation against cholera with cholera nucleo-proteid 

 prepared by Lustig's method, reports the results of an experiment in a rabbit 

 in which the animal had finally received 0.25 gram of the nucleo-proteid. The 

 serum was then tested and showed an agglutinative value in a dilution of 1 : 400. 

 By finally inoculating 0.8 of a gram of the nucleo-proteid this value was increased 

 to 1 : 1,000. A rabbit which was inoculated with the entire cholera organism 

 produced an agglutinative serum in a dilution of from 1: 1,000 to 1: 3,000. The 

 author emphasizes the fact that the injection of the nucleo-proteid causes but a 

 moderate reaction and gives rise to a high immunity which lasts for months, 

 and that the prophylactic does not readily -deteriorate. 



Friedberger and Moreschi, 15 in a study of the comparative value of the active 

 immunization of rabbits against cholera and typhoid infection obtained by 

 different methods, performed numerous experiments with cultures of the cholera 

 organism killed by diverse means and with others dried at high temperatures or 

 autolytically digested. Their conclusions in this article throw but little light 

 upon the vahie of autolytie digestion as a practicable means of obtaining the 

 immunizing substances from the spirillum for ixse in cholera prophylaxis. In 

 their conclusions regarding this subject, they state that with the Pfeiffer-Kolle 

 method, or with one recommended by Loeffler (in which the bacteria are killed 

 at 120° C), autolysis carried on at body temperature produces no distinct 

 influence upon the activity of the antigens in immunization, and that certainly 

 these substances do not become increased. In another portion of their article they 



12 Publications of the Bureau of Government Laboratories, Manila (1904), 

 16, 1, and J. Infect. Dis. (1905), 2, 107. 



1$ Centrbl. f. Bakteriol. Orig. (1905), 38, 584. 

 "Ibid, 39, 106. 

 "Ibid, 453. 



