Campus Units

Natural Resource Ecology and Management

Document Type

Article

Publication Version

Accepted Manuscript

Publication Date

5-29-2019

Journal or Book Title

Integrative and Comparative Biology

DOI

10.1093/icb/icz065

Abstract

Host competence, or how well an individual transmits pathogens, varies substantially within and among animal populations. As this variation can alter the course of epidemics and epizootics, revealing its underlying causes will help predict and control the spread of disease. One host trait that could drive heterogeneity in competence is host tolerance, which minimizes fitness losses during infection without decreasing pathogen load. In many cases, tolerance should increase competence by extending infectious periods and enabling behaviors that facilitate contact among hosts. However, we argue that the links between tolerance and competence are more varied. Specifically, the different physiological and behavioral mechanisms by which hosts achieve tolerance should have a range of effects on competence, enhancing the ability to transmit pathogens in some circumstances and impeding it in others. Because tissue-based pathology (damage) that reduces host fitness is often critical for pathogen transmission, we focus on two mechanisms that can underlie tolerance at the tissue level: damage-avoidance and damage-repair. As damage-avoidance reduces transmission-enhancing pathology, this mechanism is likely to decrease host competence and pathogen transmission. In contrast, damage-repair does not prevent transmission-relevant pathology from occurring. Rather, damage-repair provides new, healthy tissues that pathogens can exploit, likely extending the infectious period and increasing host competence. We explore these concepts through graphical models and present three disease systems in which damage-avoidance and damage-repair alter host competence in the predicted directions. Finally, we suggest that by incorporating these links, future theoretical studies could provide new insights into infectious disease dynamics and host-pathogen coevolution.

Comments

This is a manuscript of an article published as Henschen, Amberleigh E., and James S. Adelman. "What Does Tolerance Mean for Animal Disease Dynamics When Pathology Enhances Transmission?." Integrative and comparative biology (2019). doi: 10.1093/icb/icz065. Posted with permission.

Copyright Owner

The Authors

Language

en

File Format

application/pdf

Available for download on Friday, May 29, 2020

Published Version

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