Predictive factors of imported malaria in 272 febrile returning travelers seen as outpatients

Abstract

Background. We conducted a prospective study to evaluate the aetiologies of fever in returning travelers and to identify the clinical and laboratory factors predictive of malaria in travelers returning from tropical areas with fever. Methods. We included those consulting for fever appearing less than 3 months after return. Destinations were classified according to the visited continent (America including Caribbean, Asia, Africa, Oceania). We prospectively included all returning travelers consulting our department between November 2002 and May 2003 for health problems and investigated those presenting fever within 3 months after return from a tropical country. We then conducted a case control study to identify factors predictive of malaria. Control group was defined as febrile travelers without malaria. Results. A total of 272 febrile travelers were included. They were 152 tourists (55.9%), 58 immigrants (21.3%), 33 expatriates (12.1%), and 29 business travelers (10.7%). Besides malaria (54 cases), the main diagnosis in the 218 controls were bacterial enteritis, bacterial pneumonia, infectious cellulitis, pyelonephritis, prostatis, dengue fever, primary viral infection (HIV, EBV, CMV, parvovirus B19), and tuberculosis. Multivariate regression analysis showed correlations between malaria and travel to Africa (OR = 11.9), abdominal pain (OR = 14.1), vomiting (OR = 19.4), myalgia (OR = 6.3), inadequate prophylaxis (OR = 10.1), and platelets <150,000/μL (OR = 25.2). Conclusions. Our results suggest that no single clinical or biological feature had both good sensitivity and specificity to predict malaria in febrile travelers seen as outpatients within 3 months after returning from the tropics. © 2010 International Society of Travel Medicine.