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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.
Symptoms of malaria and yellow fever are similar. Patients may experience chills, headaches, back pain, fever, muscle aches, fatigue, nausea and weakness. For malaria, the virus has an incubation period of 7 to 30 days; for yellow fever, the incubation period is 3 to 6 days. For both diseases, symptoms generally appear in a week.