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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    Certain Considerations on the Causation and Course of Epidemics. By John Brownlee, M.D. The mathematical and biological theory of epidemics has hitherto been treated by few writers, but it is a priori a branch of the theory of chance, and the mathematics of the theory of chance once properly applied should afford a solution applicable to all epidemics. The ideas which underlie the theory of chance are, however, complex, and there are not many workers who have both the mastery of this theory and the necessary epidemiological knowledge to permit of its application. The results of a preliminary investigation into this subject I propose to lay before you to-night. It makes no claim to be more than a beginning, but as far as it goes it shows that the main laws which regulate epidemics are as simple as the law of gravitation, though the application of them to the diverse conditions which govern epidemics is often of considerable complexity. The chief difficulty arises from the fact that there is no means at present known of directly measuring the power of infectivity possessed by an organism. The value and variation of this power can only be dis- covered by making various assumptions, and testing the truth or error of these assumptions by the degree of correspondence which the results obtained on each assumption have with the actual facts. This is, of course, but the general method by which the theory of chance has been discovered, as when it is applied to games of chance or to coin- tossing where some hours of experiment settle at once whether theory and fact have any correspondence.