Phlebotomine Sand Flies in Southern Thailand: Entomological Survey, Identification of Blood Meals and Molecular Detection of Trypanosoma spp.

An entomological survey at rural and cavernicolous localities in four provinces in southern Thailand provided 155 blood-fed females of sand flies (Diptera: Psychodidae) that were identified based on morphological characters as Idiophlebotomus asperulus ( n = 19), Phlebotomus stantoni ( n = 4), P. argentipes ( n = 3), Sergentomyia anodontis ( n = 20), S. barraudi ( n = 9), S. hamidi ( n = 23), S. hodgsoni ( n = 4), S. hodgsoni hodgsoni ( n = 32), S. indica ( n = 5), S. iyengari ( n = 2), S. khawi ( n = 17), S. silvatica ( n = 11) and Sergentomyia sp. ( n = 6). The dominant species in this study was S. hodgsoni hodgsoni , which was collected specifically in a Buddha cave. Screening for DNA of parasitic protozoans revealed eight specimens (5.16%) of four species ( S. barraudi , S. indica , S. khawi and Id. asperulus ) positive for Trypanosoma sp., while no Leishmania spp. DNA was detected. Blood meals of engorged females were identified by PCR-Restriction Fragment Length Polymorphism (PCR-RFLP) assay on a fragment of cytochrome b ( cyt b ) gene with a success rate 36%, humans, dogs, and rats being determined as sources of blood. Bloodmeal analysis of two Trypanopsoma -positive females ( S. barraudi and Sergentomyia sp.) identified blood from dogs and humans, respectively. Our findings indicate that S. barraudi , S. indica , S. khawi and Id. asperulus may be incriminated in circulation of detected Trypanosoma spp.