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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 and malaria are both viral conditions given to humans by mosquitoes and share similar symptoms. Malaria is one of the most common viral diseases in the world and both diseases are an important concern for public health officials in developing nations.