Blackwater fever is a severe complication of the malaria infection in which the Plasmodium parasites transmitted by mosquitoes cause the red blood cells burst in the bloodstream (hemolysis), releasing hemoglobin directly into the blood vessels and into the urine, frequently leading to kidney failure. The disease was first linked to malaria by the Sierra Leone Creole physician John Farrell Easmon in his 1884 pamphlet entitled The Nature and Treatment of Blackwater Fever. Easmon coined the name "blackwater fever" and was the first to successfully treat such cases following the publication of his pamphlet. The disease is much less common today than it was before 1950.
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