Amphibian chytrid or Bd (Batrachochytrium dendrobatidis) was accidentally introduced to Mallorcan Midwife Toads (Alytes muletensis) before their release into the wild in 1991. Bd was not even known to science before the late 90’s. It’s just another example of how disease can be spread unkowingly through conservation efforts. Luckily, the toads seem to be somewhat resistant to the fungus.