Bloodmeal Identification in Field-Collected Sand Flies From Casa Branca, Brazil, Using the Cytochrome b PCR Method.

PCR-based identification of vertebrate host bloodmeals has been performed on several vectors species with success. In the present study, we used a previously published PCR protocol followed by DNA sequencing based on primers designed from multiple alignments of the mitochondrial cytochrome b gene used to identify avian and mammalian hosts of various hematophagous vectors. The amplification of a fragment encoding a 359 bp sequence of the Cyt b gene yielded recognized amplification products in 192 female sand flies (53%), from a total of 362 females analyzed. In the study area of Casa Branca, Brazil, blood-engorged female sand flies such as Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1924), and Nyssomyia whitmani (Antunes & Coutinho, 1939) were analyzed for bloodmeal sources. The PCR-based method identified human, dog, chicken, and domestic rat blood sources.

Molecular Detection of Leishmania DNA in Wild-Caught Phlebotomine Sand Flies (Diptera: Psychodidae) From a Cave in the State of Minas Gerais, Brazil.

Leishmania spp. are distributed throughout the world, and different species are associated with varying degrees of disease severity. In Brazil, Leishmania transmission involves several species of phlebotomine sand flies that are closely associated with different parasites and reservoirs, and thereby giving rise to different transmission cycles. Infection occurs during the bloodmeals of sand flies obtained from a variety of wild and domestic animals, and sometimes from humans. The present study focused on detection of Leishmania DNA in phlebotomine sand flies from a cave in the state of Minas Gerais. Detection of Leishmania in female sand flies was performed with ITS1 PCR-RFLP (internal transcribed spacer 1) using HaeIII enzyme and genetic sequencing for SSUrRNA target. The survey of Leishmania DNA was carried out on 232 pools and the parasite DNA was detected in four: one pool of Lutzomyia cavernicola (Costa Lima, 1932), infected with Le. infantum (ITS1 PCR-RFLP), two pools of Evandromyia sallesi (Galvão & Coutinho, 1939), both infected with Leishmania braziliensis complex (SSUrRNA genetic sequencing analysis), and one pool of Sciopemyia sordellii (Shannon & Del Ponte, 1927), infected with subgenus Leishmania (SSUrRNA genetic sequencing analysis). The present study identified the species for Leishmania DNA detected in four pools of sand flies, all of which were captured inside the cave. These results represent the first molecular detection of Lu cavernicola with Le infantum DNA, Sc sordellii with subgenus Leishmania DNA, and Ev sallesi with Leishmania braziliensis complex DNA. The infection rate in females captured for this study was 0.17%.