Chytridiomycosis caused by Batrachochytrium dendrobatidis is the deadliest infectious disease of vertebrates in history. Understanding this crisis reveals the intersection of conservation and individual animal welfare.
Chytridiomycosis has caused the deaths of an uncountable number of individual amphibians - likely billions of animals across multiple continents. The welfare dimension of this crisis is rarely discussed: the death from chytridiomycosis is neither instantaneous nor painless. The progressive disruption of skin function causes metabolic abnormalities and ultimately cardiac failure over a period that can last days to weeks. Individual frogs and salamanders dying of this disease are experiencing a prolonged, distressing physiological crisis. The scale of individual animal suffering caused by the introduction of this pathogen - through the global amphibian trade that humans created and managed without biosecurity - is an ecological and welfare catastrophe without precedent.