Diversity, natural infection and blood meal sources of phlebotomine sandflies (Diptera, Psychodidae) in the western Brazilian Amazon

Molecular e serological detection of Leishmania infantum (Trypanosomatida: Trypanosomatidae) in domestic dogs in Manaus city, Amazonas, Brazil

Leishmaniasis are zoonosis widely spread in Brazil, caused by the protozoan of the genus Leishmania, which includes several species. The disease manifests itself in the visceral or tegumentary form, and the main reservoir is the dogs. Manaus is the largest city in the Brazilian Amazon region, and despite the importance of the municipality, practically nothing is known about leishmaniosis in humans and animals. The objective of this study was to evaluate the occurrence and risk factors associated with the presence of Leishmania infantum in domiciliated dogs from Manaus. Molecular (polymerase chain reaction) and serological (immunofluorescent antibody test) methods were used as an indication of the circulation of the parasite. Blood samples for 154 domiciled dogs were obtained, and prevalence ratio and analysis of the variables were performed. Serum antibodies anti-Leishmania spp. were detected in 20.8% (95% CI: 14.4%-27.2%). Access to the street and zone of residence (P < 0.01) were associated with higher seropositivity. Molecular diagnosis for L. infantum detected positivity in 60 (39%) of the 154 (95% CI: 31.3%-46.7%) animals, and the variables street access, contact with dogs, and zone of residence were associated with higher frequencies of positivity (P < 0.05). Both serology and molecular diagnosis detected positive dogs in the municipality. This is the first description of the circulation of L. infantum infecting dogs in Manaus. As the municipality is classified as nonendemic, studies of isolation and characterization of the isolate must be done urgently.

Molecular and morphometric study of Brazilian populations of Psychodopygus davisi

In this study, we analysed the molecular and morphometric differences of several populations of the putative sand fly vector Psychodopygus davisi (Root, 1934) (Diptera, Psychodidae, Phlebotominae) in Brazil. We amplified the 658 base pair fragments of the DNA barcoding region-cytochrome c oxidase subunit 1 (COI) gene-for 57 specimens of P. davisi and three specimens of Psychodopygus claustrei (Abonnenc, Léger & Fauran, 1979). We merged our data with public sequences of the same species available from GenBank. Then, the combined dataset-87 sequences and 20 localities-was analysed using population structure analysis and different species delimitation approaches. Geometric morphometry of wings was performed for 155 specimens of P. davisi populations from the North, Midwest and Southeast Brazilian regions, analysing the differences in centroid sizes and canonical variates. Molecular analysis indicated high intraspecific genetic distance values for P. davisi (maximum p distance = 5.52%). All algorithms identified P. davisi and P. claustrei as distinct molecular taxonomic units, despite the low interspecific distance (p distance to the nearest neighbour = 4.79%). P. davisi sequences were split into four genetic clusters by population structure analysis and at least five genetic lineages using intermediate scenarios of the species delimitation algorithms. The species validation analysis of BPP strongly supported the five-species model in our dataset. We found high genetic diversity in this taxon, which is in agreement with its wide geographic distribution in Brazil. Furthermore, the wing analysis showed that specimens from the Southeast Region of Brazil are different from those in the North and the Midwest. The evolutionary patterns of P. davisi populations in Brazil suggest the presence of candidate species, which need to be validated in future studies using a more comprehensive approach with both genomic data and morphological characters.

Trichophoromyia auraensis: evidence for cryptic species and first record in the state of Maranhão, Brazil

Trichophoromyia auraensis (Mangabeira, 1942) (Diptera, Psychodidae, Phlebotominae) has a wide geographic distribution in the western region of the Amazon biome, where it is a putative Leishmania vector. Here, we reported for the first time a population of this species in the Brazilian state of Maranhão, in the eastern Amazon, from which we DNA-barcoded and compared with previously processed specimens from Acre State, in the western Amazon. For this, we analyzed the DNA barcoding fragment (658 bp) of the mitochondrial cytochrome c oxidase subunit I (COI) gene and the nuclear internal transcribed spacer 2 (ITS2) of Trichophoromyia species using phylogenetic gene trees, and species delimitation algorithms. The analyses of COI barcodes showed high values of genetic distance (mean K2P = 5.17) and well-supported clades/MOTUs for the eastern and western populations of T. auraensis, which may indicate a possible complex of cryptic species. The western population of this taxon merged with the close-related sand fly Trichophoromyia velezbernali Posada-López, Galvis and Galati, 2018 from Colombia, which may be associated with the recent speciation history and introgression between these populations. These evidences should be evaluated with a more comprehensive sampling in terms of analyzed populations and molecular markers.

Data-driven predictions of potential Leishmania vectors in the Americas

The incidence of vector-borne diseases is rising as deforestation, climate change, and globalization bring humans in contact with arthropods that can transmit pathogens. In particular, incidence of American Cutaneous Leishmaniasis (ACL), a disease caused by parasites transmitted by sandflies, is increasing as previously intact habitats are cleared for agriculture and urban areas, potentially bringing people into contact with vectors and reservoir hosts. Previous evidence has identified dozens of sandfly species that have been infected with and/or transmit Leishmania parasites. However, there is an incomplete understanding of which sandfly species transmit the parasite, complicating efforts to limit disease spread. Here, we apply machine learning models (boosted regression trees) to leverage biological and geographical traits of known sandfly vectors to predict potential vectors. Additionally, we generate trait profiles of confirmed vectors and identify important factors in transmission. Our model performed well with an average out of sample accuracy of 86%. The models predict that synanthropic sandflies living in areas with greater canopy height, less human modification, and within an optimal range of rainfall are more likely to be Leishmania vectors. We also observed that generalist sandflies that are able to inhabit many different ecoregions are more likely to transmit the parasites. Our results suggest that Psychodopygus amazonensis and Nyssomia antunesi are unidentified potential vectors, and should be the focus of sampling and research efforts. Overall, we found that our machine learning approach provides valuable information for Leishmania surveillance and management in an otherwise complex and data sparse system.

Phlebotomine Fauna (Diptera: Psychodidae) and Infection by Leishmania spp. in Forest Fragments of a University Campus, Western Amazon

Forest fragments consist of important ecosystems for the maintenance of sand fly populations and Leishmania hosts. This study sought to identify the phlebotomine fauna and its infection by Leishmania spp. in forest fragments on the campus of the Federal University of Acre (UFAC), Western Amazon. Monthly collections with CDC traps were carried out from March 2020 to June 2021, in four forest fragments of UFAC. Male and female insects were processed and identified at species level. A sample of females was subjected to polymerase chain reaction (PCR) analysis to verify the presence Leishmania DNA. In total, 465 specimens were collected, of which 238 were males and 227 were females. The most frequent species were Nyssomyia antunesi (Coutinho, 1939) (47.3%), Trichophoromyia sp. (Mangabeira, 1942) (18.70%), and Ny. whitmani (Antunes & Coutinho, 1939) (8.81%). Molecular analysis detected the presence of Leishmania (Ross, 1903) DNA in a specimen of Ny. antunesi, and another one of Evandromyia walker (Newstead, 1914). The forest fragments of the university campus harbor a diverse sand fly fauna with the presence of Leishmania DNA in these insects, in addition to the presence of other species considered incriminated vectors of Leishmania parasites.

Preliminary observations of the urbanization and domiciliation of the American cutaneous leishmaniasis in Rio Branco, Acre, Western Amazon

BACKGROUND

The American cutaneous leishmaniasis (ACL) is expanding in peri-urban environments.

METHODS

An entomological survey was conducted in the area of the occurrence of an autochthonous urban case of ACL. Sandflies and a parasitological slide of the human case were submitted for molecular diagnosis.

RESULTS

Nyssomyia whitmani and Ny. antunesi were the most frequently collected species. Ny. whitmani and Bichromomyia flaviscutellata were positive for Leishmania guyanensis and L. lainsoni, respectively. The human case tested positive for L. lainsoni.

CONCLUSIONS

Sandflies and Leishmania parasites present in urban forest may occur frequently in nearby domiciliary environments; thus, these areas must be monitored.

Revisiting the cave-dwelling sand flies (Diptera, Psychodidae, Phlebotominae) from Brazil: Diversity and potential role in the transmission of Leishmania Ross, 1903 (Kinetoplastida: Trypanosomatidae)

Brazilian caves, one of the many tourist attractions of the country, may act as a shelter for insects, such as sand flies (Diptera: Psychodidae), natural hosts of various microorganisms including parasites of the genus Leishmania Ross, 1903. In the last decades, with the increasing global need for sustainable development, ecotourism has emerged as one of the major activities in Brazil. However, the constant monitoring in environmentally protected areas is not often carried out, endangering visitors and professionals, especially due to the occurrence of zoonoses. Several sand fly species have already been recorded in Brazilian caves, drawing attention to the possibility of Leishmania transmission at this ecotope. Indeed, this current systematic review summarizes the fauna of cave-dwelling sand flies in Brazil, focusing on their biological behaviour and the occurrence of potential vectors of Leishmania parasites.

Updating the knowledge of sand flies (Diptera, Psychodidae) in Rondônia State, Brazil

Background

Sandflies are insects important for the transmission cycles of the leishmaniases. Despite being studied since the 1960s in the State of Rondônia (Brazil), several gaps exist regarding our working knowledge of these insects. This study aimed to construct an up-to-date database of sandflies using complementary information from the speciesLink database and the scientific literature, as well as to elaborate integrated abundance maps. We identified 153,155 records of sandflies captured in Rondônia between 1965-2021; after exclusion, 147,258 reports (speciesLink - 3,408, Rondônia studies - 143,850) associated with 15 genera and 140 species were mapped. The most abundant species observed were Psychodopygusdavisi (Root, 1934) (43,818 records), Nyssomyiawhitmani (Antunes & Coutinho, 1939) (12,594), Psychodopyguscarrerai (Barretto, 1946) (11,840), Psychodopygushirsutus (Mangabeira, 1942) (9,676), Nyssomyiaantunesi (Coutinho, 1939) (8,847), Trichophoromyiaubiquitalis (Mangabeira, 1942) (5,505), Psychodopygusgeniculatus (Mangabeira, 1941) (4,644), Pintomyianevesi (Damasceno & Arouck, 1956) (4,140), Trichophoromyiaauraensis (Mangabeira, 1942) (3,579), Psychodopyguscomplexus (Mangabeira, 1941) (2,659), Nyssomyiafraihai (Martins, Falcão & Silva, 1979) (2,504) and Bichromomyiaflaviscutellata (Mangabeira, 1942) (1,418). A total of 20 records of Leishmania detection corresponded to eight sand fly species. The present dataset provides updated information on the distribution of sandflies of Rondônia, including those considered potential vectors of Leishmania, which should prove useful to guide future studies.

New information

The present study provides an extensive dataset built from all studies reporting phlebotomine sandflies in the Brazilian State of Rondônia. Online distribution maps can aid scientists who wish to consult the updated list of sand fly species and view the distribution of these insects, as well as those considered potential vectors of Leishmania. The results of the present study can serve as the basis for future studies on sandflies conducted in the State.

Blood Feeding Sources of Nyssomyia antunesi (Diptera: Psychodidae): A Suspected Vector of Leishmania (Kinetoplastida: Trypanosomatidae) in the Brazilian Amazon

Present work aimed to identify blood feeding sources and attempt to detect Leishmania DNA in Nyssomyia antunesi, suspected vector of Leishmania sp., from a park in the urban center of Belém, the capital of Pará State, in the Brazilian Amazon. Entire bodies and gut contents of Ny. antunesi engorged females, previously captured in the urban park with Centers for Disease Control (CDC) light traps and aspiration on tree bases, were subjected to Leishmania and vertebrate DNA detection through amplification of the Leishmania mini-exon and vertebrate cytochrome b (cyt b) gene regions, respectively. The quality of DNA extraction from entire bodies was ensured through amplification of the dipteran cyt b region. The vertebrate cyt b amplicons were sequenced and compared with those available on GenBank. A maximum likelihood phylogenetic tree was constructed to assess the clustering patterns of these sequences. Leishmania DNA was not detected. The sequences of 13 vertebrate cyt b amplicons were considered informative, exhibiting similarity and clustering with the following six vertebrate species: Dasyprocta leporina (1), Cuniculus paca (1), Tamandua tetradactyla (4), Choloepus didactylus (4), Pteroglossus aracari aracari (2), Homo sapiens (1). The samples of D. leporina and C. paca were obtained from the CDC canopy, whereas the others were by aspiration from tree bases. The present results revealed the eclectic and opportunist blood-feeding behavior of Ny. antunesi, with birds and mammals, these last ones acting as potential reservoirs for Leishmania species, distributed throughout the vertical forest strata.

Identification of blood meal sources in species of genus Rhodnius in four different environments in the Brazilian amazon

Chagas disease is a zoonotic disease caused by the hemoflagellate Trypanosoma cruzi and transmitted primarily by triatomine vectors. Triatomines are hematophagous insects that feed on a variety of vertebrate hosts. The Chagas disease transmission cycle is closely related to the interactions between vectors, parasites, and vertebrate hosts. Knowledge of triatomine food sources is critical to understanding Chagas disease transmission dynamics. The aim of this study was to identify blood meal sources used by triatomines from different environments in the Brazilian Amazon. A total of 25 captures were conducted in four environments. Triatomine specimens were captured on palm trees and were identified by morphological and morphometric characters. Blood meal sources identification was conducted using a traditional PCR followed by Sanger sequencing of mtDNA cytb gene. Sequencing was successful in 167 specimens and a total of 21 blood meal sources were identified: two reptilians, six birds, and 13 mammals. Among these 21 species, three (Tamandua tetradactyla, Didelphis marsupialis and Rattus rattus) are considered reservoir of T. cruzi. Knowledge of the relationship between triatomines and possible reservoirs can help to elucidate the enzootic cycle of T. cruzi in the Amazon region and guide control strategies for Chagas disease transmission in that region.

Use of light emitting diodes (LEDs) are effective and useful for sand fly ecoepidemiology studies in an Amazonian environment

One strategy to identify transmission foci is based on vector monitoring, and efficient methods are important for vector control. Our study evaluated different light sources (red, green, ultraviolet, blue, and incandescent light) to capture sand fly in Porto Velho, Brazil. We also evaluated Leishmania and blood meal sources in females. A total of 1,943 individuals were identified in 45 species level-taxa, with Trichophoromyia ubiquitalis (Mangabeira) (n=364), Nyssomyia antunesi (n=241), Bichromomyia flaviscutellata (Mangabeira) (n=222), and Psychodopygus davisi (Root) (n=148) being the most abundant. Incandescent light captured most individuals (n=589), followed by blue (n=471), green (n=452), ultraviolet (n=281) and red (n=150). No significant difference was observed between the species composition and lights (PERMANOVA: Pseudo F = 1.29, p = 0.14, NMDS: Stress 0.18). The Shannon and Simpson indices demonstrated a high diversity captured using all lights. Our data demonstrated that LEDs are alternative devices for sand fly capture, with blue and green LEDs presenting similar results to incandescent light. 53 pools were analyzed, only one pool was positive for kDNA and hsp70 targets [Nyssomyia fraihai (Martins, Falão & Silva)] and identified as Endotrypanum spp., suggesting that other trypanosomatids may circulate in the locality. Choloepus hoffmanni (two-toed sloth) Peters, Homo sapiens Linnaeus, Proechimys gardneri (Gardner's spiny rat) Da Silva, and Tamandua tetradactyla (lesser anteater) (Linnaeus) were blood meal sources identified in females, increasing the knowledge about sources used by these insects.

Trypanosomatids in Phlebotomine Sand Flies (Diptera: Phlebotominae) From Anthropic and Sinantropic Landscapes in a Rural Settlement in the Brazilian Amazon

Trypanosomatids (Kinetoplastida:Trypanosomatidae) protozoa are a diverse group of obligate parasites. The genera Trypanosoma and Leishmania are the most studied because of their medical importance. This work aims to evaluate the effects of anthropization processes on the composition of the phlebotomine sand fly fauna and the natural infection by Trypanosomatids, with emphasis on Leishmania. At all 3,186 sand flies were collected, distributed in 13 genera and 52 species, being Ny. umbratilis the most abundant species. There was no difference in the diversity between canopy and soil environments. The species abundance and richness were higher in the forest environment while species diversity and evenness were highest in the forest edge. The ITS1 region was used by PCR-RFLP to identify the fragment profiles of Leishmania species, followed by genetic sequencing. Here were analyzed 100 pools of female sand flies, being six positive for DNA parasite. PCR-RFLP fragment patterns similar to Endotrypanum sp. were observed in Nyssomyia anduzei, Psychodopygus amazonensis and Lutzomyia gomezi, and those fragments similar to Leishmania (Leishmania) amazonensis were observed in Bichromomyia flaviscutellata. ITS1 sequencing confirmed the presence of Leishmania sp. in Bi. flaviscutellata, and Leishmania (Viannia) naiffi in Ny. anduzei, Psychodopygus amazonensis, and Lu. gomezi. This is the first record of Lu. gomezi and Ps. amazonensis infection by L. naiffi in the State of Amazonas. These results show the trypanosomatid infection in sandflies from different landscapes in a rural settlement, and the finding of species infected with L.(V.) naiffi suggest that they can develop a role in the transmission cycle of leishmaniasis.

Sand fly fauna and molecular detection of Leishmania species and blood meal sources in different rural environments in western Amazon

Cutaneous Leishmaniasis (CL) is a disease caused by Leishmania species and transmitted by the bites of infected female sand fly species. The diversity of these insects in Rondônia State (where CL is the predominant form) is large but unexplored, and consequently the vector species are unknown. The purpose of this study was to evaluate the sand fly fauna in two environments (forest fragment and peridomicile) in rural areas of four municipalities of the state, DNA amplification of Leishmania species and the presence of blood meal sources for these insects. After identifying the species, sample coverage was applied to estimate the fauna coverage in each environment. Females were used to amplify and detect Leishmania DNA and blood meal sources, then posteriorly identified by sequencing. A total of 1706 individuals were included in 61 species, which was a sample coverage of 97% for the forest fragments (56 species), whereas 98% was observed (32 species) in peridomiciles. Next, 41 pools were prepared from 1227 females, and none were positive for Leishmania DNA. We observed 160 engorged females (forest fragments: 21, peridomiciles: 139) belonging to females of the Antunesi complex and another eight species. Two of these females were positive for Leishmania braziliensis-DNA: one in the Antunesi complex and one in Psychodopygus hirsutus. Seven blood meal sources were identified by sequencing analysis: Bos taurus and Sus scrofa from the peridomiciles, and Dasypus novemcinctus, Pecari tajacu, Philander canus, Plecturocebus bernhardi, and Tamandua tetradactyla from the forest fragments. Our data confirmed the feeding behavior of field-caught sand flies and could contribute to our understanding about local vectors and possible reservoirs in the transmission of Leishmania spp.

Identification of Bloodmeals from Sand Flies (Diptera: Psychodidae) Collected in the Parque Nacional do Viruá, State of Roraima, Brazil

The transmission of pathogens that cause leishmaniases occurs by the bite of female sand flies (Diptera: Psychodidae) in their vertebrate hosts, which makes the identification of their bloodmeal sources an important step for the control and epidemiology of these diseases. In Brazil, the state of Roraima has a great diversity of sand flies, vertebrate hosts, and protozoan Leishmania, but little is known about the host blood-feeding preferences of sand flies. Thus, we evaluated the bloodmeal sources of sand flies collected from their sylvatic habitats in Parque Nacional do Viruá, Roraima. Fieldwork was carried-out between 13th and 18th August 2019 using CDC light traps. Sand flies were slide-mounted and morphologically identified using the head and last segments of the abdomen. Engorged females had their DNA extracted, followed by amplification and sequencing of the cytochrome b (cytb) molecular marker for vertebrates. Sequences were analyzed and compared with those from GenBank using the BLASTn search tool, in addition to the reconstruction of a phylogenetic tree to demonstrate the clustering pattern of these sequences. A total of 1,209 sand flies were identified, comprising 20 species, in which the most abundant were Psychodopygus ayrozai (Barretto and Coutinho) (42.10%) and Psychodopygus chagasi (Costa Lima) (26.22%). Bloodmeal source identification was successfully performed for 34 sand flies, that confirm four vertebrate species, being the most abundant the armadillo Dasypus novemcinctus Linnaeus, 1758 (Cingulata: Dasypodidae).

Occurrence of Leishmania infection in the immediate geographic region of Ji-Paraná, Rondônia State, Brazil

INTRODUCTION

This study evaluated the epidemiology of American cutaneous leishmaniasis in the immediate region of Ji-Paraná, Rondônia State.

METHODS

Samples and epidemiological data were collected from 105 patients.

RESULTS

Leishmania infection was observed in 58 (55.2%) patients, and Leishmania braziliensis was present in 82.9% of the 41 sequenced samples. Infected patients were predominantly male (93.1%). Leishmania infection was twice as prevalent among rural inhabitants versus urban inhabitants. Lesions were more frequent in the upper limbs (arms/hands, 41.82%).

CONCLUSIONS

The present data corroborate the zoonotic profile of cutaneous leishmaniasis; this information could help to improve surveillance and control strategies.

First molecular evidence of frogs as a food source for sand flies (Diptera: Phlebotominae) in Brazilian caves

Genus and species of phlebotomine sand flies have been recorded and described in caves in Brazil, but no study has provided the food source used by sand flies in these environments. Herein, we identified the blood source used by sand fly species in caves located at "Quadrilátero Ferrífero" (QF), Minas Gerais state. Specimens were manually collected near or on anurans inside ferruginous caves in Serra do Gandarela National Park and Serra do Rola Moça State Park. Males and females were placed in vials with 70% alcohol and stored at -10°C. Females engorged, after specific identification, had DNA extracted and followed for PCR amplification using specific primers. Sequencing was analyzed in the GenBank and Barcode of Life. A total of 198 specimens were collected (107 females and 91 males), all of them belonging to species Sciopemyia aff. microps (88.89%), Sciopemyia sordellii (10.61%), or Martinsmyia oliveirai (0.50%). When it comes to the females, 89 were S. aff. microps and 18 S. sordellii. Nineteen engorged females of S. aff. microps were analyzed and most of them (n=18) presented blood from Bokermannohyla martinsi and one contained blood from Scinax fuscovarius. The blood present in engorged females of S. sordellii (n=4) was from B. martinsi. Sciopemyia genus specimens are commonly found in collections carried out inside natural caves, but this was the first study to prove that females of this genus feed on cold-blooded animals in nature. HIGHLIGHTS: • Here we proved that sand flies feed in cold-blooded animals in in Brazilian caves. • Females of the Sciopemyia genus were for the first time found feeding in natural habitats. • Anurans of the family Hylidae were identified as source by molecular analyzes. • Insect bloodmeal identification can help assessing the fauna in several biomes. • This is the first record of S. aff. microps in caves of Brazil.

Species diversity and blood meal sources of phlebotomine sand flies (Diptera: Psychodidae) from Los Tuxtlas, Veracruz, Mexico

Phlebotomine sand flies can transmit several species of the genus Leishmania, that cause leishmaniasis, a serious neglected tropical disease worldwide. Although Mexico is an endemic country for the disease, studies on the biology, ecology, and the identification of blood meal sources of phlebotomine sand flies in some states remain unexplored. For this reason, this study aimed to evaluate the species diversity of sand flies, and identify their blood meal sources in the Biosphere Reserve Los Tuxtlas, Veracruz, an area with a high prevalence of Leishmania infantum. The cumulative sampling effort of sand flies covered 300 trap-nights between March 2011 and May 2013. For estimating species diversity, we calculated the species richness (q = 0), the diversity of the species (q = 1) and the dominant species (q = 2). To identify the blood meal sources, we amplified and sequenced a fragment of ≈400 bp of the vertebrate Cytb gene. A total of 951 specimens belonging to 15 species were collected. Psathyromyia aclydifera and Psychodopygus panamensis were the most abundant species. We were able to identify seven terrestrial vertebrate species, among which human beings were the most common source of the blood meal. In this study, relevant information on the structure of sand fly populations and their blood meal sources was obtained, providing basic and important information about the interactions between sand flies, hosts and Leishmania species.

Biting Midges in Jamari National Forest, in the Brazilian Amazon, With 12 New Records of Culicoides Species (Diptera: Ceratopogonidae) for the State of Rondônia

Culicoides biting midges are small hematophagous flies, some species of which transmit pathogens to livestock and humans. In the Brazilian Amazon Basin, Culicoides diversity has remained largely unexamined. Jamari National Forest (JNF) is a conservation area in Rondônia State where research and environmental education are conducted in conjunction with the protection of natural resources, and the recovery of degraded areas. The present study augments our knowledge of Culicoides diversity in JNF. The survey collected 640 individuals from 41 species; 632 individuals were collected by HP light trap and 8 were collected by the BG Sentinel trap. Twelve species are first-time records for Rondônia: Culicoides acotylus Lutz, Culicoides albuquerquei Wirth & Blanton, Culicoides baniwa Felippe-Bauer, Culicoides bricenoi Ortiz, Culicoides brownei Spinelli, Culicoides carsiomelas Wirth & Blanton, Culicoides debilipalpis Lutz, Culicoides forattinii Ortiz, Culicoides ginesi Ortiz, Culicoides profundus Santarém, Felippe-Bauer & Trindade, Culicoides pseudoreticulatus Santarém, Felippe-Bauer & Castellón, and Culicoides spurius Santarém, Felippe-Bauer & Trindade. The most abundant species were Culicoides glabrior Macfie, Culicoides pseudodiabolicus Fox, Culicoides debilipalpis, Culicoides quasiparaensis Clastrier, and Culicoides brownei Spinelli. The present study updates the Culicoides species count in Rondônia to 55, and highlights the importance of JNF as a hotbed for biting midge diversity.

Detection of Leishmania species (Kinetoplastida, Trypanosomatidae) in phlebotomine sand flies (Diptera, Psychodidae) from Porto Velho, Northern Brazil

Cutaneous Leishmaniasis (CL) is a vector-borne disease caused by Leishmania species and transmitted by infected female sand flies. CL is widely distributed in Brazil, but knowledge about vectors and transmission cycles could be complex according to localities. The sand fly fauna in Rondônia State is extensive, diverse, and largely unexplored. Although the state records a mean of 1,000 CL cases per year, the vectors of CL are unknown. The aim of this study was to assess phlebotomine sand fly fauna composition using diversity indexes (Shannon [H'] and Simpson [1/D]) and to detect the prevalence of Leishmania infection to verify potential vectors in three ecotopes: (i) forest fragment (FF), (ii) forest edge (FE), and (iii) peridomicile (PE). Captures were performed in four rural districts in the municipality of Porto Velho. A total of 7,026 specimens were captured comprising 72 species, and individuals classified in subgenus level. Overall, the most abundant species were Lutzomyia davisi (n: 1,105), Lutzomyia melloi (n: 760), Lutzomyia auraensis (n: 738) and Lutzomyia antunesi (n: 479). Fauna was most diverse in the FF ecotope (H' = 20.2, 1/D = 11.2), followed by the FE (H' = 18.0, 1/D = 10.1) and PE (H' = 16.6, 1/D = 10.1) ecotopes. Leishmania DNA was detected in 24 of 232 pools. In every ecotope, Leishmania naiffi DNA was identified in the following sand fly species: Lu. antunesi, Lu. davisi, Lu. hirsuta hirsuta, Lu. shawi, Lu. sordellii and Lu. (Trichophoromyia) spp. This observation may indicate that a Le. naiffi transmission focus is present in the study localities. In addition, Leishmania lainsoni was detected in Lutzomyia (Trichophoromyia) spp. Our findings show that sand fly fauna in the study localities is diverse, that Leishmania parasites are circulating in all three ecotopes, and that some sand fly species may be implicated in the transmission of Leishmania to humans in localities evaluated.

Leishmania infection and blood sources analysis in Phlebotomus chinensis (Diptera: Psychodidae) along extension region of the loess plateau, China

BACKGROUND

Visceral leishmaniasis (VL) was one of the most important parasitic diseases in China, caused by Leishmania protozoans and transmitted by sand flies. Recently VL cases have reappeared in China, including the extension region of the Loess Plateau. The purpose of this study was to collect fundamental data on the host-vector VL system in the Loess Plateau to assist in the development of prevention and control measures.

METHODS

Sand flies were collected by light traps from rural areas in Shanxian, Henan, China in 2015, as well as in Wuxiang and Yangquan, Shanxi, China in 2017. The blood sources of sand flies were analyzed by PCR detecting the host-specific mitochondrial cytochrome b (mtDNA cyt b) gene fragments. Leishmania infection in sand flies was detected by amplifying and sequencing ribosomal DNA internal transcribed spacer 1 (ITS1). The Leishmania specific antibodies in the sera of local dogs were detected by ELISA kit.

RESULTS

Blood sources showed diversity in the extension region of the Loess Plateau, including human, chicken, dog, cattle, pig and goat. Multiple blood sources within a sand fly were observed in samples from Yangquan (17/118, 14.4%) and Wuxiang (12/108, 11.1%). Leishmania DNA was detected in sand flies collected from Yangquan with minimum infection rate of 1.00%. The ITS1 sequences were conserved with the Leishmania donovani complex. The positive rate of Leishmania specific antibodies in dogs was 5.97%.

CONCLUSIONS

This study detected the blood sources and Leishmania parasites infection of sand flies by molecular methods in the extension region of Loess Plateau, China. A high epidemic risk of leishmaniasis is currently indicated by the results as the infection of Leishmania in sand flies, the extensive blood sources of sand flies including humans, and positive antibody of Leishmania in local dog sera. Given the recent increase of VL cases, asymptomatic patients, dogs and other potential infected animals should be screened and treated. Furthermore, the density of sand flies needs to be controlled and personal protection should be strengthened.

Vertical stratification of sand fly diversity in relation to natural infections of Leishmania sp. and blood-meal sources in Jamari National Forest, Rondônia State, Brazil

BACKGROUND

Almost 1000 cases of American cutaneous leishmaniasis have been registered yearly in Rondônia State, Brazil. Little is known about the Leishmania transmission cycle (vectors and reservoirs) in the state. This study aimed to evaluate sand fly fauna from two vertical stratification layers in order to identify potential vectors and their blood-meal sources.

METHODS

The study was conducted in Jamari National Forest. Sand flies were collected in the canopy (15 m) and at ground level (1 m) using HP light traps during four months, February, April, August and October, 2018. Insects were identified to the species level, and females were subjected to DNA extraction and PCR targeting minicircle kDNA and hsp70 (for Leishmania detection and species identification), and cytb (to identify blood-meal sources). Exploratory data analysis was used to determine mean of abundance and species richness between stratifications. The hsp70 and cytb sequences were analyzed and compared with sequences from GenBank.

RESULTS

Overall, 68 species were identified from 15,457 individuals. On the Potosi trail, 7531 individuals of 49 species were collected; canopy captures totaled 6463 individuals of 46 species, while ground captures totaled 1068 individuals of 38 species. On the Santa Maria trail, 7926 individuals of 61 species were collected; canopy captures totaled 6136 individuals of 51 species, while ground captures totaled 1790 individuals of 53 species. A total of 23 pools were positive for kDNA (canopy n = 21, ground n = 2). Only two samples were sequenced for hsp70 (both in canopy); one sequence exhibited similarity with Leishmania braziliensis (Lutzomyia davisi pool) and another with L. naiffi (Lu. antunesi pool). The cytb fragment was amplified in 11 of 86 samples. Sample sequencing identified cytb DNA from 5 blood-meal sources: Micrastur gilvicollis, Psophia viridis, Tamandua tetradactyla, Homo sapiens and Choloepus didactylus.

CONCLUSIONS

Sand fly fauna is more diverse in the canopy than at ground level. Factors such as blood-meal sources, resting sites, and abiotic components probably contribute to high abundance in the canopy. Our results reinforce the possibility that Lu. antunesi and Lu. davisi participate in Leishmania transmission in forest environments and may play an important role in transmission from sylvatic to human hosts.

New Records of Phlebotomine Sand Flies (Diptera: Psychodidae) From the Western Brazilian Amazon and the Description of the Female of Pintomyia fiocruzi

An entomological survey was conducted in several localities of Rondônia State, and new records were obtained for seven sand fly species: Evandromyia apurinan Shimabukuro, Figueira & Silva, 2013, Evandromyia carmelinoi (Ryan, Fraiha, Lainson & Shaw, 1986), Micropygomyia echinatopharynx Andrade-Filho, Galati, Andrade & Falcão, 2004, Nyssomyia urbinattii Galati & Galvis, 2012, Pintomyia duckei Oliveira, Alencar & Freitas, 2018, Psathyromyia pradobarrientosi (Le Pont, Matias, Martinez & Dujardin, 2004), and Sciopemyia vattierae (Le Pont & Desjeux, 1992). Herein, we also describe the female of Pintomyia fiocruzi Pereira Júnior, Pessoa, Marivalva & Medeiros, 2019. The female has spermathecae with a detached apical ring similar to the spermathecae of Pintomyia serrana (Damasceno & Arouck, 1949), Pintomyia odax (Fairchild & Hertig, 1961), Pintomyia ottolinai (Ortiz & Scorza, 1963), and Pintomyia robusta (Galati, Cáceres & Le Pont, 1995). Here, we provide characters to separate Pi. fiocruzi from Pi. serrana and Pi. odax. Pintomyia ottolinai has a trans-Andean distribution and Pi. robusta has not been found in Brazil and in our studies, we associated the females found in this study with Pi. fiocruzi males found at the same collection sites. Our findings highlight the importance of entomological fauna surveys and demonstrate the need for taxonomists to study species diversity in Rondônia. This study increases the number of sand fly species recorded in Rondônia to 143.

Complex ecological interactions across a focus of cutaneous leishmaniasis in Eastern Colombia: novel description of Leishmania species, hosts and phlebotomine fauna

This study aimed to analyse the patterns of diversity, blood sources and Leishmania species of phlebotomines in a focus of cutaneous leishmaniasis in Arboledas, Eastern Colombia. In total, 1729 phlebotomines were captured in two localities (62.3% Siravita and 37.7% Cinera) and five environments of Norte de Santander. We identified 18 species of phlebotomines: Pintomyia ovallesi (29.8%), Psychodopygus davisi (20.3%), Pi. spinicrassa (18.5%) and Lutzomyia gomezi (15.8%) showed the highest abundance. Species diversities were compared between Cinera (15.00) and Siravita (20.00) and among five microenvironments: forest remnants (19.49), coffee plantations (12.5), grassland (12.99), cane plantations (11.66) and citrus plantations (12.22). Leishmania DNA was detected in 5.8% (80/1380) of females, corresponding mainly to Pi. ovallesi (22/80; 27.2%), Lu. gomezi (17/80; 21.3%) and Pi. spinicrassa (11/80; 13.8%). Leishmania species were 63.1% L. braziliensis, 18.5% L. panamensis, 13.2% L. infantum and 6.1% L. amazonensis. The most frequent feeding sources were Homo sapiens (50%), Bos taurus (13.8%) and Canis lupus familiaris (10.3%). This focus of cutaneous leishmaniasis has a high diversity of Leishmania-carrying phlebotomines that feed on domestic animals. The transmission of leishmaniasis to human hosts was mainly associated with Lu. gomezi, Pi. ovallesi and L. braziliensis.