Wildlife diseases are theatening wild animal populations. This project will focus on the diseases chytridiomycosis and diphtheria. Chytridiomycosis is a fungal skin in amphibians that has demonstrated its role in the decline of at least 501 amphibian species, including 90 presumed extinctions, all over the world. Diphtheria, caused by the zoonotic Corynebacterium ulcerans, is an emerging disease in hedgehogs in Europe, causing severe population declines. We will study the pathogenesis of both diseases in order to be able to develop mitigation measures that can halt ongoing declines.