title: Within-host parasite dynamics, emerging trade-off, and evolution of virulence with immune system.
abstract: Virulence is an evolutionary paradox because parasites never benefit from their host's death. The adaptive explanation of virulence is classically based upon the existence of physiological constraints that create a trade-off between parasites' epidemiological traits (virulence, transmissibility, and clearance). Here we develop an epidemiological model where infections are dynamic processes and we demonstrate how these dynamics generate a trade-off between emerging epidemiological parameters. We then study how host's immune strength modifies this trade-off and hence influences virulence evolution. We found that in acute infections, where parasites are engaged in a race with immune cells, immunity restrains more the duration of the infection than its intensity. As a consequence parasites evolve to provoke more virulent but shorter infections in strongly immunized hosts.
authors.affiliation: Laboratoire Génome, Populations, Interactions, Adaptation, UM2-IFREMER-CNRS UMR 5000, Université Montpellier II-CC 063, Bâtiment 13, RdC, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France. jbandre@crit.univ-montp2.fr
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: André
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Ferdy
authors.forename: Bernard
authors.initials: B
authors.lastname: Godelle
mesh_terms: D005075:Biological Evolution; D006790:Host-Parasite Interactions; D007113:Immunity, Innate; D008954:Models, Biological; D014774:Virulence