Amphibian populations around the world have been affected by two pathogenic fungi within the phylum Chytridiomycota. Batrachochytrium dendrobatidis (Bd) has infected hundreds of species and led to widespread declines and some species extinctions. Batrachochytrium salamandrivorans (Bsal) has devastated some native European salamanders, especially the iconic fire salamanders (Salamandra salamandra). Comparative genomic studies show that Bd is more diverse and widespread than previously thought, and global lineages occur together allowing for the development of hybrid lineages. New studies raise the concern of greater pathogenesis if both Bd and Bsal infect the same host. Although amphibians possess robust immune defenses, co-infected and many single-infected hosts seem unable to mount effective immune responses. A strong defense may actually be harmful. Analysis of Bd and Bsal secretions documents small metabolites that signal high density to limit their growth and to suppress adaptive immune defenses, thus enabling a stealth presence in the skin compartment.

世界各地的两栖动物种群都受到壶菌门内两种病原真菌的影响。Batrachochytrium dendrobatidis ( Bd ) 已经感染了数百种物种，并导致了广泛的衰退和一些物种的灭绝。Batrachochytrium salamandrivorans ( Bsal ) 已经摧毁了一些欧洲本土的蝾螈，尤其是标志性的火蝾螈 ( Salamandra salamandra )。比较基因组研究表明，Bd比以前认为的更加多样化和广泛，并且全球谱系一起出现，允许杂交谱系的发展。如果Bd和Bsal感染同一主机。尽管两栖动物拥有强大的免疫防御能力，但合并感染和许多单一感染的宿主似乎无法产生有效的免疫反应。强大的防御实际上可能是有害的。对Bd和Bsal分泌物的分析记录了小代谢物，它们发出高密度信号以限制其生长并抑制适应性免疫防御，从而使皮肤隔室中的隐形存在。