Influenza-Like Illness as an Atypical Presentation of Falciparum Malaria in a Traveler from Africa

Background: According to the Centers for Disease Control and Prevention, the risk of fatal malaria in non-endemic countries can be reduced greatly if physicians are alert to the atypical presenting features of malaria. Case Report: A patient arrived in the United States from Nigeria 2 days before presenting to an emergency department (ED) with sore throat, dry cough, fever (without chills), headache, and severe lethargy. A presumptive diagnosis of influenza-like illness was made. The patient improved after symptomatic treatment and was therefore discharged from the ED; she continued with her travel. After 24 h, the patient presented to our ED with symptoms suggestive of meningitis. The analysis of the cerebrospinal fluid was normal. A peripheral blood smear was diagnostic of falciparum malaria (parasitic index of 1). Because the disease was acquired from a chloroquine-resistant endemic area, the patient was treated with quinine and doxycycline, and she responded well. Conclusion: In this era of heightened influenza alert, differentiating between influenza-like illness and malaria can be challenging. Patients with a history of travel to a malaria-endemic area in the preceding year should undergo a complete blood count (CBC), hepatic panel, and blood smear. Due to logistic reasons, the result of a blood smear may not be available immediately. Thrombocytopenia and hyperbilirubinemia each has a positive predictive value of 95% in the presumptive diagnosis of malaria. Patients who do not appear sick, and those who have a normal CBC and hepatic panel, may be treated symptomatically and discharged (with follow-up advised). Those with a presumptive diagnosis of malaria or unclear speciation should be admitted for anti-malarial therapy.