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Spatial structure, transmission modes and the evolution of viral exploitation strategies.

ABSTRACT: Spatial structure and local migration are predicted to promote the evolution of less aggressive host exploitation strategies in horizontally transmitted pathogens. Here we explore the effect of spatial structure on the evolution of pathogens that can use both horizontal and vertical routes of transmission. First, we analyse theoretically how vertical transmission can alter evolutionary trajectories and confirm that space can impede the spread of virulent pathogens. Second, we test this prediction using the latent phage ? which transmits horizontally and vertically in Escherichia coli populations. We show that the latent phage ? wins competition against the virulent mutant ?cI857 in spatially structured epidemics, but loses when spatial structure is eroded. The vertical transmission of phage ? immunizes its local host pool against superinfection and prevents the spread of the virulent ?cI857. This effect breaks down when mixing facilitates horizontal transmission to uninfected hosts. We thus confirm the importance of spatial structure for the evolutionary maintenance of prudent infection strategies in latent viruses.

SUBMITTER: Berngruber TW

PROVIDER: S-EPMC4405370 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Spatial structure, transmission modes and the evolution of viral exploitation strategies.

Berngruber Thomas W TW Lion Sébastien S Gandon Sylvain S

PLoS pathogens 20150421 4

Spatial structure and local migration are predicted to promote the evolution of less aggressive host exploitation strategies in horizontally transmitted pathogens. Here we explore the effect of spatial structure on the evolution of pathogens that can use both horizontal and vertical routes of transmission. First, we analyse theoretically how vertical transmission can alter evolutionary trajectories and confirm that space can impede the spread of virulent pathogens. Second, we test this predictio ...[more]

PMID: 25898324

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Spatial structure, transmission modes and the evolution of viral exploitation strategies.

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Spatial structure, transmission modes and the evolution of viral exploitation strategies.

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