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Malaria - and its cousin, yellow fever - had significant implications during the war and the debilitating consequences of the disease were already certain before the Civil War had started in earnest and well before its final history had been written.
What is yellow fever? Yellow fever is a disease caused by a flavivirus that is transmitted by the bite of an infected mosquito. It gets its name from the yellowing of the skin and eyes (jaundice) that occurs when the virus attacks the liver. Yellow fever can be prevented by a vaccine.