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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.
1 Yellow fever is a viral hemorrhagic infection transmitted by mosquitoes of the Aedes genus. 2  Yellow fever has and continues to affect the equatorial tropics and is believed to have been imported to the Americas with the West African slave trade.