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The present study is the second and last part of the study that investigated the fauna and behavior of sand flies in areas prone to cutaneous leishmaniasis outbreaks, in the State of Rio de Janeiro, in the municipality of Paraty. To collect the sand flies, CDC and Shannon light traps were used, installed in the peridomiciliary and forest areas, and manual suction tubes on the walls of the home and in the animal shelters. A total of 102,937 sand flies, belonging to nine genera and 23 species were captured from October 2009 to September 2012. Regarding the monthly frequency of sand flies, the period of highest density was from November to March, with a maximum peak in January. The lowest density was observed in June and July. In the studied area, the species of epidemiological importance, Nyssomyia intermedia, Pintomyia fischeri, Migonemyia migonei and Nyssomyia whitmani, were found in all months of the year, a period in which residents may be in contact with these vectors of the etiological agent of cutaneous leishmaniasis.

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Sand flies are dipterans of medical importance, as some species are vectors of American visceral leishmaniasis (AVL). The municipality of João Pessoa (Paraíba, northeastern Brazil), is an endemic region for AVL, having high rates of human and canine cases. The main objective was to evaluate the sand fly fauna among forest fragments and built areas, and its relationship with environmental conditions. HP light traps were placed in the studied areas from March 2019 to July 2021. A total of 2141 specimens of phlebotomines were captured, comprising nine genera and ten species. Temperature and humidity were significant and positive only in built areas. The diversity composition among forest fragments and built areas was different and the AVL vector, Lutzomyia longipalpis, was the most prevalent species in built areas. The study showed that the built areas present differences in their richness and diversity of sand flies in relation to forest fragments, concluding that the conservation of forest areas, even if urban fragments, favors the diversity of phlebotomine species.

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From October 1994 to September 1996, in the municipality of Mangaratiba, Rio de Janeiro State, phlebotomines were captured on the walls of the houses by means of a manual suction tube and light traps, in the household, the peridomicile and in the forest. As it is an area undergoing a real expansion and an increment in the local tourism, with the purpose of assessing changes in the phlebotomine fauna caused by environmental changes in the region, new captures were made in the same location from October 2015 to September 2016, this time using only light traps. In the two phases of the study, a total of 6,681 phlebotomines were captured. The results indicated that Ny. intermedia and Mg. migonei are fully adapted to this anthropic environment, while Pi. fischeri was more abundant and eclectic, and was probably attracted to exercise hematophagy. Nyssomyia intermedia can be suggested as the main vector of the etiological agent of the American Tegumentary Leishmaniasis in the studied areas. Pintomyia fischeri can also transmit Leishmania braziliensis, both in the environment altered by human action, and in the wild environment. Phlebotomines were captured in greater numbers between 6 and 8 pm in the peridomicile and between 9 and 11 pm in the household. The highest densities of phlebotomines were recorded in December, January and February. Despite almost 20 years between the two studies in the municipality of Mangaratiba, there was no change in the profile of the phlebotomine fauna in general; however, there was a greater density of species of medical importance in areas that suffered environmental impacts.

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ABSTRACT From October 1994 to September 1996, in the municipality of Mangaratiba, Rio de Janeiro State, phlebotomines were captured on the walls of the houses by means of a manual suction tube and light traps, in the household, the peridomicile and in the forest. As it is an area undergoing a real expansion and an increment in the local tourism, with the purpose of assessing changes in the phlebotomine fauna caused by environmental changes in the region, new captures were made in the same location from October 2015 to September 2016, this time using only light traps. In the two phases of the study, a total of 6,681 phlebotomines were captured. The results indicated that Ny. intermedia and Mg. migonei are fully adapted to this anthropic environment, while Pi. fischeri was more abundant and eclectic, and was probably attracted to exercise hematophagy. Nyssomyia intermedia can be suggested as the main vector of the etiological agent of the American Tegumentary Leishmaniasis in the studied areas. Pintomyia fischeri can also transmit Leishmania braziliensis, both in the environment altered by human action, and in the wild environment. Phlebotomines were captured in greater numbers between 6 and 8 pm in the peridomicile and between 9 and 11 pm in the household. The highest densities of phlebotomines were recorded in December, January and February. Despite almost 20 years between the two studies in the municipality of Mangaratiba, there was no change in the profile of the phlebotomine fauna in general; however, there was a greater density of species of medical importance in areas that suffered environmental impacts.

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Males of cryptic or closely related species present great morphological variation in their genitalia, whereas females, such as those of the Chagasi Series of the Psychodopygus Mangabeira, 1941 genus, are more similar. Therefore, our aim was to study the fine structure of the male genitalia of five species of the Chagasi Series to better understand the variation in their morphology and its influence on the copulatory process. The sand fly species were captured in the following Brazilian states: Psychodopygus chagasi (Costa Lima, 1941) (Rondônia), Psychodopygus complexus (Mangabeira, 1941) (Tocantins), Psychodopygus squamiventris maripaensis (Floch & Abonnenc, 1946) (Amapá), Psychodopygus squamiventris squamiventris (Lutz & Neiva, 1912) (Amazonas), and Psychodopygus wellcomei Fraiha, Shaw & Lainson, 1971 (Pará and Ceará). Insects were stored in ethanol 70% (then dehydrated) and dry after they were sputtered with gold. The samples were observed under a scanning electron microscope. Microtrichiae, two types of trichoid sensilla, coeloconic and chaetic sensillae, were observed on the antenna of all species, with no difference between them. Only on the anepimeron of P. squamiventris squamiventris a modified 'racket'-like scale was observed. As for the male genitalia, the setae and structures of each species were fully described, such as the small setae on the paramere apex of the P. squamiventris subspecies, and the grooves present in this region and on the paramere lobe of P. complexus and P. wellcomei, which are impossible to observe with optic microscopy. New information is thus provided on the male genitalia, which can contribute to future bionomic studies of these species.

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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.

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INTRODUCTION: American cutaneous leishmaniasis (ACL) is regarded as a public health problem in the Oiapoque basin, between Brazil and French Guiana. METHODS: Data on ACL occurrence/epidemiological profile and etiology were sourced from Brazilian health services and a reference laboratory. Rainfall correlation was also analyzed. RESULTS: Majority of the ACL cases were observed in adult men working as gold miners. ACL incidence peaks appeared to be linked to periods 2 months after the dry season. Migratory flow was found to be a non-negligible complicating factor in epidemiological surveillance. CONCLUSIONS: Binational strategies are required to minimize exposure for high-risk populations.

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Abstract INTRODUCTION: American cutaneous leishmaniasis (ACL) is regarded as a public health problem in the Oiapoque basin, between Brazil and French Guiana. METHODS Data on ACL occurrence/epidemiological profile and etiology were sourced from Brazilian health services and a reference laboratory. Rainfall correlation was also analyzed. RESULTS: Majority of the ACL cases were observed in adult men working as gold miners. ACL incidence peaks appeared to be linked to periods 2 months after the dry season. Migratory flow was found to be a non-negligible complicating factor in epidemiological surveillance. CONCLUSIONS: Binational strategies are required to minimize exposure for high-risk populations.

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BACKGROUND: An entomological study was conducted in the municipality of Oiapoque (lower Oyapock River Basin) in the Brazilian side bordering French Guiana to gain information on the transmission pattern of American cutaneous leishmaniasis (ACL) in that region, presumed to reflect the classical Amazonian/Guianan enzootic scenario. METHODS: Three ecologically isolated forested areas near urban environments were surveyed during the rainy and dry seasons of 2015 and 2016, using a multi-trapping approach comprising ground-level and canopy light traps, black and white colored cloth Shannon traps and manual aspiration on tree bases. Female phlebotomines were dissected to find infections and isolate flagellates from Leishmania spp. The strains were characterized by restriction fragment length polymorphism analysis and compared with those of local ACL cases and World Health Organization reference strains. RESULTS: Nyssomyia umbratilis, Trichopygomyia trichopyga and Evandromyia infraspinosa were the most frequently found species. Findings on relative abundance, spatiotemporal vector/ACL congruence, natural infections and anthropophilic insights strengthened the Guianan classical transmission of Leishmania (Viannia) guyanensis by Ny. umbratilis and suggested further investigations for Ev. infraspinosa. Nyssomyia umbratilis showed an eclectic feeding habit, including bird blood. Ecological data and literature reports also included Psychodopygus squamiventris maripaensis and Bichromomyia flaviscutellata on the list of suspected vectors. CONCLUSIONS: These findings contributed to understanding ACL ecoepidemiology in the Amazonian/Guianan scenario. Local studies are required to better comprehend the Leishmania spp. enzootic mosaic in specific ecotopes.

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In some transmission foci of Leishmania infantum in Brazil, Lutzomyia cruzi could be considered the main vector of this pathogen. In addition, L. cruzi is a permissive vector of L. amazonensis. Its geographical distribution seems to be restricted and limited to Cerrado and Pantanal biomes, which includes some areas in Brazil and Bolivia. Considering that predicting the distribution of the species involved in transmission cycles is an effective approach for assessing human disease risk, this study aims to predict the spatial distribution of L. cruzi using a multiscale ecological niche model based in both climate and habitat variables. Ecological niche modelling was used to identify areas in South America that are environmentally suitable for this particular vector species, but its presence is not recorded. Vector occurrence records were compiled from the literature, museum collections and Brazilian Health Departments. Bioclimatic variables, altitude, and land use and cover were used as predictors in five ecological niche model algorithms: BIOCLIM, generalised linear model (logistic regression), maximum entropy, random forests, and support vector machines. The vector occurs in areas where annual mean temperature values range from 21.76°C to 26.58°C, and annual total precipitation varies from 1005 mm and 2048 mm. Urban areas were most present around capture locations. The potential distribution area of L. cruzi according to the final ecological niche model spans Brazil and Bolivia in patches of suitable habitats inside a larger climatically favourable area. The bigger portion of this suitable area is located at Brazilian States of Mato Grosso do Sul and Mato Grosso. Our findings identified environmentally suitable areas for L. cruzi in regions without its known occurrence, so further field sampling of sand flies is recommended, especially in southern Goiás State, Mato Grosso do Sul (borders with Mato Grosso, São Paulo and Minas Gerais); and in Bolivian departments Santa Cruz and El Beni.

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