Protective inoculation against cholera.

  • Haffkine, W. M. (Waldemar Mordecai), 1860-1930.
Date:
1913
Catalogue details

Licence: In copyright

Credit: Protective inoculation against cholera. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    (1) the faculty of resisting various specific substances in the animal body— agglutinines, bactericidines, alexines, bac- teriolysines—which tend to destroy the germ ; or of absorbing and thus neutralizing these substances ; or of producing others— aggressines —which seem to ward oft' and injure the protective elements of the body ; (2) the faculty of calling forth in the system of the animal the formation of the defensive substances mentioned in the foregoing paragraph, or of others of similar purpose, such as stimulines, bacteriotropines, etc.; (3) the faculty of comparatively rapid growth and multi- plication ; (4) the faculty of producing and setting free poisonous substances or toxines, which cause morbid symptoms in the animal; and so on. I believe that at present it would not be a safe procedure to consider a germ pathogenic or virulent if it possesses one or some of the above properties, singled out above the others ; or to declare an animal immune, if it resists a germ virulent in that restricted sense. A true vaccine is perhaps best defined as one which prepares the individual to face the virus in its most common manifestations in outbreaks. I shall have occasion to touch again upon this subject later. GENERAL AND SPECIAL FEATURES OF THE PROBLEM UNDER CONSIDERATION. Peculiarities dependent on the Nature op the Germ. The above observations go to show that the immunizing power of a germ varies with its virulence ; and in order to produce a vaccine of given definite efficacy, a strain of virus is required of as definite a degree of pathogenic strength. The germ of cholera being of the varying and unstable nature mentioned above, the problem of anti-cholera inoculation, as a measure of practical application, becomes dependent on the possibility of steadying that virus on an adequate level of potency, namely, on a level sufficient for conferring on man immunity from epidemic cholera,