First description of Leishmania (Viannia) infection in Evandromyia saulensis, Pressatia sp. and Trichophoromyia auraensis (Psychodidae: Phlebotominae) in a transmission area of cutaneous leishmaniasis in Acre state, Amazon Basin, Brazil

Abstract

Studies on the sandfly fauna to evaluate natural infection indexes are still limited in the Brazilian Amazon, a region with an increasing incidence of cutaneous leishmaniasis. Here, by using a multiplex polymerase chain reaction directed to Leishmania kDNA and hybridisation, we were able to identify L. (Viannia) subgenus in 12 out of 173 sandflies captured in the municipality of Rio Branco, Acre state, revealing a positivity of 6.94%. By sequencing the Leishmania 234 bp-hsp70 amplified products from positive samples, infection by L. (V.) braziliensis was confirmed in five sandflies: one Evandromyia saulensis, three Trichophoromyia auraensis and one Pressatia sp. The finding of L. (Viannia) DNA in two Ev. saulensis corresponds to the first record of possible infection associated with this sandfly. Moreover, our study reveals for the first time in Brazil, Th. auraensis and Pressatia sp. infected by L. (Viannia) parasites.

An overview of the sandfly fauna (Diptera: Psychodidae) followed by the detection of Leishmania DNA and blood meal identification in the state of Acre, Amazonian Brazil

“…as possible vectors in the state of Acre. (26,29,54) As recently discussed, the putative vector importance of some species of the Trichophoromyia genus (including those found in Acre) seems to be increasing, (28) but as far as we know our results are the first to demonstrate the man-biting behavior of specimens of this genus. As mentioned before, the females identified as Trichophoromyia probably belong to Th.…”

Molecular Identification of Leishmania spp. in Sand Flies (Diptera: Psychodidae, Phlebotominae) From Ecuador

“…for the first time in Perú. Araujo-Pereira et al (2017) also reported Pressatia sp. infected with Leishmania brazilienzis .…”

Increasing putative vector importance of Trichophoromyia phlebotomines (Diptera: Psychodidae)

“…ruifreitasi by L. (V.) guyanensis and L. (V.) braziliensis in Brazil. Interestingly, Araújo-Pereira et al (25) found 9/96 individually processed and unambiguously identified Th. auraensis positive to Leishmania kDNA, with three of them revealed as L. (V.) braziliensis.…”

“…Martinez et al (19) Th. auraensis Valdivia et al (20) Ogawa et al (23) Araújo-Pereira et al (25) Resadore et al (26) Th. auraensis/Th.…”

“…The raising question on the putative vector importance of Trichophoromyia is also likely to be biased toward the marked increase in the general list of suspected vectors of leishmaniasis in the New World, (1,3,4) which has been supported in the last years, mainly due to the results of PCR-based techniques for diagnosing Leishmania DNA targets within pooled or individually processed phlebotomines. Integrative molecular methodological approaches let us to include suspected vector species from phlebotomine genera with little or even null association with Leishmania, such as Pintomyia, (35) Pressatia, Evandromyia, (25,31) Martinsmyia, and Micropygomyia; (36) in our view, care must be taken on interpreting these intriguing results. Even considering established natural infection, quantification of the parasitic load and/or demonstration of infective forms would certainly present a further step toward improving knowledge on putative Leishmania vectors inferred exclusively through DNA-based findings.…”