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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.
Yellow fever is a disease spread to humans by mosquitoes. The effects of yellow fever on the human body usually include fever, chills, and vomiting. Some people also experience backache and headache. Dehydration is one of the biggest dangers associated with yellow fever, but other life-threatening effects of yellow fever are sometimes experienced.