Imported malaria. Clinical presentation and examination of symptomatic travelers

The diagnosis of malaria in nonendemic countries presents a continuing challenge. Increasing physician awareness of the variability in its clinical presentation will improve clinical management and health outcomes.

Charts of patients in whom malaria was diagnosed at two hospital-based tropical disease centers between September 1, 1980, and December 31, 1991, were reviewed.

Of a total of 482 cases, 182 were caused by Plasmodium falciparum and 246 by Plasmodium vivax. Fifty-two patients with P falciparum malaria were hospitalized; 13 were classified as having severe falciparum malaria. Nineteen patients with P vivax malaria required hospitalization. The only death was caused by P vivax. Chemoprophylaxis was used by, or prescribed for, 46% of patients; however, of these, only half were compliant in taking their medication. Eighty-seven percent of patients with falciparum malaria presented within 6 weeks of return from travel to an endemic area. One third of patients with P vivax malaria presented more than 6 months after travel. The average time between onset of symptoms and physician contact was 6.7 days. Diagnosis was often delayed in those who sought care outside the referral center. Almost all patients had a history of fever, but only half were febrile at presentation. Presenting symptoms and signs were non-specific. Fifty percent of patients were thrombocytopenic. Other laboratory abnormalities were mild.

Since the presentation of malaria is vague and nonspecific, the diagnosis should be considered in any appropriately symptomatic patient with a history of travel to a malaria-endemic area, and appropriate testing should be done. Up-to-date information on chemoprophylaxis should be provided to all travelers to malaria-endemic regions.