Evolution of virulence: interdependence, constraints, and selection using nested models.

Michael A Gilchrist; Daniel Coombs

doi:10.1016/j.tpb.2005.07.002

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Evolution of virulence: interdependence, constraints, and selection using nested models.

Michael A Gilchrist·Daniel Coombs

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Abstract

Natural selection acts on virus populations at two distinct but interrelated levels: within individual hosts and between them. Studies of the evolution of virulence typically focus on selection acting at the epidemiological or between-host level and demonstrate the importance of trade-offs between disease transmission and virulence rates. Within-host studies reach similar conclusions regarding trade-offs between transmission and virulence at the level of individual cells. Studies which examine selection at both scales assume that between- and within-host selection are necessarily in conflict. We explicitly examine these ideas and assumptions using a model of within-host viral dynamics nested within a model of between-host disease dynamics. Our approach allows us to evaluate the direction of selection at the within- and between-host levels and identify situations leading to conflict and accord between the two levels of selection.

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Host-Parasite Interactions Humans Models, Genetic Selection, Genetic Virulence Viruses Journal Article Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't

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Michael A Gilchrist, Daniel Coombs. 2005-09-29. Evolution of virulence: interdependence, constraints, and selection using nested models.. https://doi.org/10.1016/j.tpb.2005.07.002

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