Known as ‘St. Anthony’s fire’, ‘sacred fire’, ’demon’s fire’ and ‘invisible fire,’ Ergotism is a medieval disease that was given it’s name from one of the key symptoms. In some iterations of the disease the sufferer’s skin blisters and turns black, as if burned by fire, but with no associated pain. What the individual is actually suffering is the gangrenous form of ergot poisoning, a type of fungal poisoning caused by the ergot fungus which grows on rye. When the rye grains are ground to flour and eaten as bread or porridge the consumer becomes poisoned.
Symptoms: (Convulsive) Degeneration of the nervous system causes anxiety, vertigo, aural/visual hallucinations, and the sensation of being bitten or burned; stupor, convulsions, and psychosis. (Gangrenous) Constriction of the blood vessels causes reddening and blistering of skin, then blackening, with itching and burning, and finally necrosis.
Result: 40% mortality. Lingering symptoms, including mental impairment, among survivors.