Are novel or locally adapted pathogens more devastating and why?: Resolving opposing hypotheses Journal Article uri icon



  • There is a rich literature highlighting that pathogens are generally; better adapted to infect local than novel hosts, and a separate; seemingly contradictory literature indicating that novel pathogens pose; the greatest threat to biodiversity and public health. Here, using; Batrachochytrium dendrobatidis, the fungus associated with; worldwide amphibian declines, we test the hypothesis that there is; enough variance in novel host-pathogen outcomes to pose substantial risk; of pathogen introductions despite local adaptation being common. Our; continental-scale, common garden experiment and global-scale; meta-analysis demonstrate that local amphibian-fungal interactions; result in higher pathogen prevalence, pathogen growth, and host; mortality, but novel interactions led to strikingly variable; consequences with the greatest risk occurring when susceptible hosts and; virulent strains interacted. Thus, while most pathogen introductions are; benign, enough variance exists in novel host-pathogen outcomes that; moving organisms around the planet greatly increases the chance of; pathogen introductions causing profound harm.

publication date

  • June 13, 2023

has restriction

  • green

Date in CU Experts

  • June 21, 2023 4:01 AM

Full Author List

  • Sauer E; Venesky M; McMahon T; Cohen JM; Bessler S; Brannelly L; Brem F; Halstead N; Hyman O; Johnson P

author count

  • 14

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