Certain considerations on the causation and course of epidemics / by John Brownlee.

  • Brownlee, John, 1868-1927.
Date:
1909
Catalogue details

Licence: In copyright

Credit: Certain considerations on the causation and course of epidemics / by John Brownlee. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    in the year 1721. This town at the beginning of the epidemic contained about 5,000 people not protected by a previous attack of small-pox, and of these 4,500 were attacked. This epidemic may thus be fairly con- sidered as one in which the disease ceased because there was no sus- ceptible material left, and though it does not accurately correspond to the previous diagram, yet it shows a considerable resemblance to it. This epidemic is, however, an almost unique example. In figure C A, An epidemic constructed on the hypothesis that the infectivity remains constant and that the disease dies out from lack of susceptible persons ; B, Epidemic of smallpox in Boston, U.S.A., in 1721, showing epidemic dying out, partly from lack of susceptible people ; C, Epidemic constructed on the hypothesis that the infectivity decreases at the rate of geometrical progression ; D, Epidemic of measles in Glasgow in 1808, showing that the decline of an epidemic tends to be longer than the ascent. the form of epidemic is given which would result if the organism lost infectivity at the rate of the geometrical progression. It is symmetrical, as may be seen, and bears a very considerable resemblance to what is