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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 mosquito-borne viral disease. The disease occurs in tropical and subtropical areas and can affect both sexes, all ages and races. Jungle yellow fever, of tropical Central and South America, occurs predominantly among adult males 20 to 40 years old who are exposed in the tropical forests.