The impact of host immune status on the within-host and population dynamics of antigenic immune escape.

Published

Journal Article

Antigenically evolving pathogens such as influenza viruses are difficult to control owing to their ability to evade host immunity by producing immune escape variants. Experimental studies have repeatedly demonstrated that viral immune escape variants emerge more often from immunized hosts than from naive hosts. This empirical relationship between host immune status and within-host immune escape is not fully understood theoretically, nor has its impact on antigenic evolution at the population level been evaluated. Here, we show that this relationship can be understood as a trade-off between the probability that a new antigenic variant is produced and the level of viraemia it reaches within a host. Scaling up this intra-host level trade-off to a simple population level model, we obtain a distribution for variant persistence times that is consistent with influenza A/H3N2 antigenic variant data. At the within-host level, our results show that target cell limitation, or a functional equivalent, provides a parsimonious explanation for how host immune status drives the generation of immune escape mutants. At the population level, our analysis also offers an alternative explanation for the observed tempo of antigenic evolution, namely that the production rate of immune escape variants is driven by the accumulation of herd immunity. Overall, our results suggest that disease control strategies should be further assessed by considering the impact that increased immunity--through vaccination--has on the production of new antigenic variants.

Full Text

Duke Authors

Cited Authors

  • Luo, S; Reed, M; Mattingly, JC; Koelle, K

Published Date

  • October 2012

Published In

Volume / Issue

  • 9 / 75

Start / End Page

  • 2603 - 2613

PubMed ID

  • 22572027

Pubmed Central ID

  • 22572027

Electronic International Standard Serial Number (EISSN)

  • 1742-5662

International Standard Serial Number (ISSN)

  • 1742-5689

Digital Object Identifier (DOI)

  • 10.1098/rsif.2012.0180

Language

  • eng