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BackgroundNotifications concerning American Cutaneous Leishmaniasis have increased in recent years in the state of Acre, Brazil. Despite identification of distinct Leishmania species isolated from cutaneous lesions, there are still no records of visceral leishmaniasis in the state. However, studies on the sand fly fauna in this region are still limited.FindingsInsects were collected from April 2011 to April 2012, using HP light traps distributed in four residential areas and one recreational area in Rio Branco, Capital of the State of Acre in the Amazon region of Brazil. A total of 456 sand flies were collected, comprising 256 females and 200 males. Taxonomic identification revealed 16 Phlebotominae genera and 23 species, as follows: Trichophoromyia auraensis, Nyssomyia whitmani, Nyssomyia antunesi, Pressatia choti, Evandromyia saulensis, Evandromyia walkeri, Evandromyia begonae, Migonemyia migonei, Pintomyia serrana, Psychodopygus paraensis, Sciopemyia sordelii, Migonemyia pusilla, Pintomyia nevesi, Brumptomyia avellari, Micropygomyia acanthopharynx, Micropygomyia micropyga, Pintomyia odax, Lutzomyia sherlocki, Pressatia calcarata, Pressatia duncanae, Bichromomyia flaviscutellata, Evandromyia bourrouli and Evandromyia bacula. From this group, Tr. auraensis and Ny. whitmani were the most abundant species in both forested areas and the peridomiciliary environment.ConclusionsWe find that the sand fly fauna in the urban and peri urban areas of Rio Branco is very diverse comprising 23 species, as diverse as that in areas of primary forest. Some species, such as Nyssomyia whitmani, Ny. antunesi and Bichromomyia flaviscutellata are known vectors of parasites responsible for cutaneous leishmaniasis, and Trichophoromyia auraensis is a putative vector in this Amazonian region.

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.

Protozoan parasites, such as Leishmania spp., are the causative agents of many insect-borne infectious diseases with medical and veterinary importance. Leishmaniasis, caused by Leishmania spp., is transmitted by female phlebotomine sand flies. In the Alentejo region of Portugal, located at the north of Algarve, cases of human and canine leishmaniasis caused by Leishmania infantum have been notified. However, no recent studies regarding the sand fly fauna in the region are available. We therefore aimed to explore the phlebotomine sand fly species found in both, Évora and Beja Districts, to gain an insight about the leishmaniasis epidemiology in these areas. After the identification of the insect species, PCR molecular tests were used to assess L. infantum infection rate in the sand fly captured females, together with the analysis of blood meal sources of the insect vectors. One Sergentomyia minuta female was positive for L. infantum infection and another for human blood as a meal source. The occurrence of this phlebotomine species infected with L. infantum may suggest that, in the Mediterranean basin, leishmaniasis epidemiology is changing. Also, if the importance of S. minuta for the zoonotic and anthroponotic cycle of leishmaniasis is later proven, the strategies to control its vector will inevitably to be rethought.

These results are congruent with the previous reports in Acre and Bolivia, revealing L. braziliensis as the most prevalent species. L. guyanensis identification also corroborates with the epidemiology of the disease in the Amazon Basin.

In the border region between Brazil and French Guiana, American cutaneous leishmaniasis is a worrisome public health issue, and entomological studies are required there to better identify classical and putative emerging transmission patterns. The present study aimed to detect and characterize Leishmania DNA in the phlebotomine population of Oiapoque (Amapá State, Brazil). Phlebotomines were captured in anthropized and wild environments in the outskirts of Oiapoque municipality, using CDC light traps installed in vertical (ground/canopy level) and horizontal (peridomicile/extradomicile/forest-edge/forest) strata. Captured specimens were identified according to their morphology. Females were processed for Leishmania DNA detection and characterization using a multiplex polymerase chain reaction targeting kinetoplast DNA (kDNA) and the phlebotomine cacophony gene. The kDNA positive samples were characterized by cloning and sequencing the Leishmania 234 bp- hsp70 gene. Among the 3957 phlebotomine specimens captured, 26 pooled female samples were positive for Leishmania ( Viannia ) spp. DNA. Sequencing analysis allowed species-specific identification of L . ( V .) braziliensis DNA in Trichophoromyia ininii , Bichromomyia flaviscutellata , Nyssomyia umbratilis , and Evandromyia infraspinosa , and L . ( V .) guyanensis DNA in Ny . umbratilis . A pooled sample of Ny . umbratilis was positive for both L . ( V .) braziliensis and L . ( V .) guyanensis DNA. The present study provided additional information regarding ACL ecology in Oiapoque, highlighting the presence of L . ( V .) braziliensis DNA in different phlebotomine species. The epidemiological implications of these findings and the determinant incrimination of L . ( V .) braziliensis as proven vectors in that region must be clarified. In this regard, studies on Leishmania spp. infection and suggestive anthropophilic behavior of associated phlebotomines need to be prioritized in entomological surveillance.

The subfamily Phlebotominae comprises important insects for public health. The use of complementary tools such as molecular taxonomy is necessary for interspecific delimitation and/or discovery of cryptic species. Here, we evaluated the DNA barcoding tool to identify different species in the southwestern Brazilian Amazon. For this, we collected sand flies in forest fragments along the highway BR-317, in the municipality of Brasiléia, state of Acre, Brazil. The specimens were DNA-barcoded using a fragment of the cytochrome c oxidase subunit I (COI) gene. The sequences were analyzed to generate K2P pairwise genetic distances and a Neighbour-joining tree. The sand fly barcodes were also clustered into Molecular Operation Taxonomic Units (MOTU) using Automatic Barcode Gap Discovery (ABGD) approach. A total of 59 COI sequences comprising 22 nominal species and ten genera were generated. Of these, 11 species had not been sequenced before, thus being new COI sequences to science. Intraspecific genetic distances ranged between 0 and 4.9%, with Pintomyia serrana presenting the highest values of genetic distance, in addition to having been partitioned into three MOTUs. Regarding the distances to the nearest neighbour, all species present higher values in relation to the maximum intraspecific distance, in addition to forming well supported clusters in the neighbour-joining analysis. The DNA barcoding approach is useful for the molecular identification of sand flies from Brasiléia, state of Acre, and was efficient in detecting cryptic diversity of five species which can be confirmed in future studies using an integrative approach. We also generated new COI barcodes for Trichophoromyia auraensis, Nyssomyia shawi, and Psychodopygus paraensis, which may play a role in the transmission of Leishmania spp. in the Brazilian Amazon.

Background Leishmaniases are vector borne diseases caused by Leishmania spp. parasites transmitted by female sandflies (Diptera: Psychodidae) whose geographic distribution is influenced by environmental factors. Among the main tools for studying the distribution of vector species, modeling techniques are used to analyze the influence of climatic and environmental factors on the distribution of these insects and their association with human cases of the disease. Methodology/Principal findings Here, we used a multiscale ecological niche modeling approach to assess the environmental suitability of sandfly vectors of the etiological agents of Visceral (VL) and American Cutaneous Leishmaniasis (ACL) in Piauí state, northeastern Brazil, and then evaluated their relationship with human disease incidence. For this, we obtained the geographic coordinates of the vector species Lutzomyia longipalpis and Nyssomyia whitmani through literature review, online databases and unpublished records. These data were used for the development of predictive models of the distribution of both sandflies species based on climatic and environmental variables. Finally, the environmental suitability for the presence of these vectors was compared with the incidence of both the diseases at the municipality level. The final models for each sandfly species showed good predictive powers with performance metric values of 0.889 for Lu. longipalpis and 0.776 for Ny. whitmani. The areas with greater environmental suitability for the presence of these species were concentrated in the central-north region of Piauí and coincide with the location of those municipalities presenting higher incidences of VL and ACL, situated in the central-north and extreme north of the state, respectively. The south and southeast regions of Piauí state have low incidence of these diseases and presented low environmental suitability for the presence of both vectors. Conclusions/Significance We discuss how predictive modeling can guide entomological and epidemiological surveillances and recommend an increased supervision and control activities in Teresina (capital of the state of Piaui), Altos and Pedro II, in addition to other municipalities with similar social and environmental characteristics.