Clinical significance of molecular methods in the diagnosis of imported malaria in returning travelers in Serbia

Summary Objectives The goal of this study was to assess the clinical significance of conventional and PCR-based molecular diagnosis in patients with imported malaria in Serbia. Methods Giemsa microscopy, the rapid diagnostic test, and quantitative real-time PCR (qPCR) were used to detect Plasmodium species in 109 whole-blood samples from patients after their return from malaria endemic areas, including those clinically suspected for malaria ( n =97) and healthy travelers ( n =12) examined as part of epidemiological surveillance. Results A total of 45 patients were diagnosed with malaria: 42 (93.3%) by microscopy and three (6.7%) additional ones by qPCR. The agreement between the results of species-specific qPCR and microscopy was 73.3%; it was as high as 90.6% for Plasmodium falciparum infections. Follow-up analysis demonstrated persistence of Plasmodium sp DNA for a mean 6 days after the disappearance of parasitemia on microscopy. Conclusions Due to its sensitivity and specificity, qPCR is a helpful method complementary to microscopy, particularly in cases of low parasitemia. In addition, it is superior to microscopy for species identification.