Vector incrimination of sand flies in the most important visceral leishmaniasis focus in Iran.

The prevalence, host preference, and rate of Leishmania spp. infection of sand fly species are important parameters for incrimination of parasite vectors. We applied polymerase chain reaction (PCR)-based and enzyme-linked immunosorbent assay (ELISA) methods to detect Leishmania spp. parasites and blood meals within individual sand flies in the most important visceral leishmaniasis (VL) focus in northwestern Iran. Leishmania spp. minicircles (kinetoplast DNA) were found in 14 (0.9%) of 1,569 female specimens. Sequence analysis of 650 basepairs of an internal transcribed spacer ribosomal DNA gene identified L. infantum/L. donovani in 12 specimens and L. adleri-like parasites in 2 specimens. Nine (64.3%) of 14 of the Leishmania spp.-positive sand flies were Phlebotomus perfeliewi transcaucasicus. Blood meal identification of host DNA within sand flies by PCR-based and ELISA methods showed that 30% and 28%, respectively, were positive for human blood. Results of this study showed that P. perfeliewi transcaucasicus is the most prevalent, infected, and anthropophagic sand fly and plays a major role in VL transmission in the region studied.