April 24, 1995

Imported MalariaClinical Presentation and Examination of Symptomatic Travelers

Author Affiliations

From the McGill University Centre for Tropical Diseases (Drs Svenson, MacLean, and Gyorkos) and Division of Clinical Epidemiology (Dr Gyorkos), Montreal (Quebec) General Hospital; Department of Epidemiology and Biostatistics, McGill University, Montreal (Dr Gyorkos); and Tropical Disease Unit, Toronto (Ontario) Hospital (Dr Keystone). Dr Svenson is now with the Department of Emergency Medicine, University of Kentucky, Lexington.

Arch Intern Med. 1995;155(8):861-868. doi:10.1001/archinte.1995.00430080109013

Background:  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 out Methods: 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.

Results:  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 nonspecific. Fifty percent of patients were thrombocytopenic. Other laboratory abnormalities were mild.

Conclusions:  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 malariaendemic regions.(Arch Intern Med. 1995;155:861-868)