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Appropriate models for the management of infectious diseases

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Wearing, Helen J., Rohani, Pejman and Keeling, Matthew James. (2005) Appropriate models for the management of infectious diseases. PLOS Medicine, Vol.2 (No.7). pp. 621-627. ISSN 1549-1277

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Official URL: http://dx.doi.org/10.1371/journal.pmed.0020174

Abstract

Background Mathematical models have become invaluable management tools for epidemiologists, both shedding light on the mechanisms underlying observed dynamics as well as making quantitative predictions on the effectiveness of different control measures. Here, we explain how substantial biases are introduced by two important, yet largely ignored, assumptions at the core of the vast majority of such models. Methods and Findings First, we use analytical methods to show that (i) ignoring the latent period or (ii) making the common assumption of exponentially distributed latent and infectious periods (when including the latent period) always results in underestimating the basic reproductive ratio of an infection from outbreak data. We then proceed to illustrate these points by fitting epidemic models to data from an influenza outbreak. Finally, we document how such unrealistic a priori assumptions concerning model structure give rise to systematically overoptimistic predictions on the outcome of potential management options. Conclusion This work aims to highlight that, when developing models for public health use, we need to pay careful attention to the intrinsic assumptions embedded within classical frameworks.

Item Type:	Journal Article
Subjects:	Q Science > QA Mathematics R Medicine
Divisions:	Faculty of Science > Life Sciences (2010- ) > Biological Sciences ( -2010)
Library of Congress Subject Headings (LCSH):	Epidemiology -- Mathematical models
Journal or Publication Title:	PLOS Medicine
Publisher:	Public Library of Science
ISSN:	1549-1277
Date:	July 2005
Volume:	Vol.2
Number:	No.7
Number of Pages:	7
Page Range:	pp. 621-627
Identification Number:	10.1371/journal.pmed.0020174
Status:	Peer Reviewed
Publication Status:	Published
Access rights to Published version:	Open Access
Funder:	Royal Society (Great Britain), National Institutes of Health (U.S.) (NIH), Ellison Medical Foundation
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URI:	http://wrap.warwick.ac.uk/id/eprint/6730