Imported malaria in Belgrade, Serbia, between 2001 and 2009

Since 2000, travel of Serbian citizens to tropical areas has been slowly but steadily increasing. To determine the epidemiological and clinical characteristics of imported malaria in Serbia, we analyzed clinical history data of all travelers who presented at the Clinic for Infectious and Tropical Diseases in Belgrade after their return from tropical and subtropical areas between 2001 and 2009. The study series involved a total of 2981 travelers, and included both those with (847) and without (2134) health problems. Malaria was diagnosed in 102 cases (3.4% of all travelers; 12.0% of travelers with febrile episodes). Occurring at a rate of 6 to 16 cases per year, it was predominantly imported from Africa (92.2%), particularly from Equatorial Guinea (38.2%) and Nigeria (15.7%). The most frequent reason for travel was work/business. Patients were predominantly (87.3%) male, and the majority (66.7%) was between 40 and 59 years of age. A total of 15 (14.7%) patients took some form of anti-malarial chemoprophylaxis. The dominant causative species was Plasmodium falciparum (78), alone (70) or in mixed infection with P. vivax (5) and P. malariae (3). P. vivax, P. ovale and P. malariae as single agents were each identified in 11, 1 and 1 cases, respectively. Of the 11 cases in which the parasite was not detected, six appeared to be true submicroscopic cases. The clinical course of the disease was severe in 13 patients, all with falciparum malaria, of which three (2.9%) died. Rather than for all travelers, in Serbia screening for malaria should be mandatory in all travelers to endemic regions who present with fever irrespective of chemoprophylaxis history. Inadequate sensitivity of conventional diagnostic methods, illustrated by the cases of submicroscopic malaria, requires introduction of molecular diagnosis in routine practice.