Generalist pathogens maintain infectivity in numerous hosts; how this broad ecological niche impacts host–pathogen coevolution remains to be widely explored. (Bd) is a highly generalist pathogenic fungus that has caused devastating declines in hundreds of amphibian species worldwide. This review examines amphibian chytridiomycosis host–pathogen interactions and available evidence for coevolution between Bd and its numerous hosts. We summarize recent evidence showing that Bd genotypes vary in geographic distribution and virulence, and that amphibian species also vary in Bd susceptibility according to their geographic distribution. How much variation can be explained by phenotypic plasticity or genetic differences remains uncertain. Recent research suggests that Bd genotypes display preferences for specific hosts and that some hosts are undergoing evolution as populations rebound from Bd outbreaks. Taken together, these findings suggest the potential for coevolution to occur and illuminate a path for addressing open questions through integrating historical and contemporary genetic data.

中文翻译：

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通用病原体与许多宿主的共同进化：两栖类壶菌 Batrachochytrium dendrobatidis 的案例

通用病原体在众多宿主中保持感染性；这种广泛的生态位如何影响宿主与病原体的共同进化仍有待广泛探索。(Bd) 是一种高度通用的致病真菌，已导致全世界数百种两栖动物物种遭受毁灭性的​​衰退。本综述探讨了两栖类壶菌病宿主与病原体之间的相互作用以及 Bd 与其众多宿主之间共同进化的现有证据。我们总结了最近的证据，表明 Bd 基因型在地理分布和毒力方面存在差异，并且两栖动物物种的 Bd 易感性也根据其地理分布而变化。有多少变异可以通过表型可塑性或遗传差异来解释仍然不确定。最近的研究表明，Bd 基因型表现出对特定宿主的偏好，并且随着种群从 Bd 爆发中反弹，一些宿主正在经历进化。总而言之，这些发现表明了共同进化发生的潜力，并阐明了通过整合历史和当代遗传数据来解决悬而未决问题的道路。