Failure of vaccination. : An enquiry into the causes of failure in vaccination, with suggestions relative to the means of ensuring its full protective influence. / By Charles Severn.

  • Severn, Charles.
Date:
1838
Catalogue details

Licence: Public Domain Mark

Credit: Failure of vaccination. : An enquiry into the causes of failure in vaccination, with suggestions relative to the means of ensuring its full protective influence. / By Charles Severn. Source: Wellcome Collection.

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    oration;—a plant indigenous, and thriving in one soil and climate, will inevitably alter, and often dwindle away and perish when removed from its original situation and transplanted in another foreign to it; and, if it retain existence at all, by a law which appears universal, it be¬ comes changed by the novel circumstances in which it is placed, and the unaccustomed influ¬ ences to which it is exposed, from which it was in its original situation wholly exempt. The different organization of different ani¬ mals may very naturally he expected to cause differences in the results of morbid actions pe¬ culiar to each respective species, when trans¬ ferred from one species to another, as is, I think, exemplified in the vaccine disease. If this opinion be correct the degree of change and deterioration would naturally be in proportion to the length of series of that species to which it had been transferred, from the source whence it originally emanated. This is precisely the case with vaccination, the preserving influence of which appears to have been considerably greater at its first introduction, and within the first five or six years after, than it now is ; and