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Phlebotomine sand flies are the vectors of leishmaniasis, a neglected tropical disease. High-quality reference genomes are an important tool for understanding the biology and eco-evolutionary dynamics underpinning disease epidemiology. Previous leishmaniasis vector reference sequences were limited by sequencing technologies available at the time and inadequate for high-resolution genomic inquiry. Here, we present updated reference assemblies of two sand flies, Phlebotomus papatasi and Lutzomyia longipalpis. These chromosome-level assemblies were generated using an ultra-low input library protocol, PacBio HiFi long reads, and Hi-C technology. The new P. papatasi reference has a final assembly span of 351.6 Mb and contig and scaffold N50s of 926 kb and 111.8 Mb, respectively. The new Lu. longipalpis reference has a final assembly span of 147.8 Mb and contig and scaffold N50s of 1.09 Mb and 40.6 Mb, respectively. Benchmarking Universal Single-Copy Orthologue (BUSCO) assessments indicated 94.5% and 95.6% complete single copy insecta orthologs for P. papatasi and Lu. longipalpis. These improved assemblies will serve as an invaluable resource for future genomic work on phlebotomine sandflies. [ABSTRACT FROM AUTHOR]

Background: Sand fly females require a blood meal to develop eggs. The size of the blood meal is crucial for fecundity and affects the dose of pathogens acquired by females when feeding on infected hosts or during experimental membrane-feeding. Methods: Under standard laboratory conditions, we compared blood meal volumes taken by females of ten sand fly species from four genera: Phlebotomus, Lutzomyia, Migonomyia, and Sergentomyia. The amount of ingested blood was determined using a haemoglobin assay. Additionally, we weighed unfed sand flies to calculate the ratio between body weight and blood meal weight. Results: The mean blood meal volume ingested by sand fly females ranged from 0.47 to 1.01 µl. Five species, Phlebotomus papatasi, P. duboscqi, Lutzomyia longipalpis, Sergentomyia minuta, and S. schwetzi, consumed about double the blood meal size compared to Migonomyia migonei. The mean body weight of females ranged from 0.183 mg in S. minuta to 0.369 mg in P. duboscqi. In males, the mean body weight ranged from 0.106 mg in M. migonei to 0.242 mg in P. duboscqi. Males were always lighter than females, with the male-to-female weight ratio ranging from 75% (in Phlebotomus argentipes) to 52% (in Phlebotomus tobbi). Conclusions: Females of most species took a blood meal 2.25–3.05 times their body weight. Notably, the relatively tiny females of P. argentipes consumed blood meals 3.34 times their body weight. The highest (Mbl/Mf) ratios were found in both Sergentomyia species studied; females of S. minuta and S. schwetzi took blood meals 4.5–5 times their body weight. This parameter is substantially higher than that reported for mosquitoes and biting midges. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microbe surface molecules can upregulate a mucin-like gene in Lutzomyia longipalpis. • Expression of the attacin gene is triggered as a generic immune response in sand flies. • Sand fly defensin gene expression is tuned, depending on the ingested microbe molecule. The interaction between pathogens and vectors' physiology can impact parasite transmission. Studying this interaction at the molecular level can help in developing control strategies. We study leishmaniases, diseases caused by Leishmania parasites transmitted by sand fly vectors, posing a significant global public health concern. Lipophosphoglycan (LPG), the major surface glycoconjugate of Leishmania , has been described to have several roles throughout the parasite's life cycle, both in the insect and vertebrate hosts. In addition, the sand fly midgut possesses a rich microbiota expressing lipopolysaccharides (LPS). However, the effect of LPG and LPS on the gene expression of sand fly midgut proteins or immunity effectors has not yet been documented. We experimentally fed Lutzomyia longipalpis and Phlebotomus papatasi sand flies with blood containing purified LPG from Leishmania infantum , Leishmania major , or LPS from Escherichia coli. The effect on the expression of genes encoding gut proteins galectin and mucin, digestive enzymes trypsin and chymotrypsin, and antimicrobial peptides (AMPs) attacin and defensins was assessed by quantitative PCR (qPCR). The gene expression of a mucin-like protein in L. longipalpis was increased by L. infantum LPG and E. coli LPS. The gene expression of a galectin was increased in L. longipalpis by L. major LPG, and in P. papatasi by E. coli LPS. Nevertheless, the gene expression of trypsins and chymotrypsins did not significantly change. On the other hand, both L. infantum and L. major LPG significantly enhanced expression of the AMP attacin in both sand fly species and defensin in L. longipalpis. In addition, E. coli LPS increased the expression of attacin and defensin in L. longipalpis. Our study showed that Leishmania LPG and E. coli LPS differentially modulate the expression of sand fly genes involved in gut maintenance and defence. This suggests that the glycoconjugates from microbiota or Leishmania may increase the vector's immune response and the gene expression of a gut coating protein in a permissive vector. [ABSTRACT FROM AUTHOR]

Leishmania spp. are zoonotic parasites transmitted by phlebotomine sand flies, including those of the Lutzomyia genus, which can cause leishmaniases in both humans and dogs. Lutzomyia spp. are established in many countries in South and Central America and some areas of the southern United States, with suspected potential of these vectors to undergo further range expansion due to climate change. A scoping review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses Extensions for Scoping Reviews (PRISMA‐ScR) guidelines to describe the current state of knowledge on the key ecological factors associated with Lutzomyia spp. survival, reproduction and establishment. The following electronic databases were searched for eligible studies published from 1 January 1990, to the date of search, 26 April 2023: CAB Direct (CABI), MEDLINE (via Ovid), Biological Sciences Database and Environmental Sciences Database. Primary research articles that were available in English and focused on ecological factors associated with Lutzomyia spp., such as climatic and habitat factors, geographic range, seasonality and temporality, and host abundance, were eligible for inclusion in the study. Following de‐duplication, a total of 167 studies were included in Level 1 screening, 64 studies were included in Level 2 screening and 31 studies met the criteria for data extraction. Study locations included Argentina, Brazil, Colombia, Peru, Venezuela, the United States, Mexico and Canada, with some studies including multiple regions. A total of 31 different Lutzomyia spp. were assessed across these studies, with most (51.6%) of the studies focused on Lutzomyia longipalpis. Eligible studies investigated factors such as seasonality (n = 5), temperature (n = 19), precipitation (n = 13), humidity (n = 2), vegetation presence or requirements (n = 13), ecotypes (n = 7), and/or community type (i.e., urban, suburban, rural) (n = 5). Lutzomyia spp. activity was found to be higher during the rainy season, and peak when temperatures were between 20 and 25°C. Lutzomyia spp. were also found to preferentially reside in tropical or subtropical forests, which are characterised by their lack of a distinct dry season and high precipitation. This scoping review summarised the current state of the literature on the ecological factors associated with the survival, activity and reproduction of Lutzomyia spp. While there appears to be some consensus in the literature regarding some ecological requirements (such as seasonality, temperature and habitat features), overall, there is a lack of published research in this topic. This poses a significant challenge for future studies, which aim to predict the future distribution of Lutzomyia spp. in the context of climate and land use changes. Additional ecological research is urgently needed on Lutzomyia spp. given their relevance to both human and animal health. [ABSTRACT FROM AUTHOR]

Abstract Background Sand fly females require a blood meal to develop eggs. The size of the blood meal is crucial for fecundity and affects the dose of pathogens acquired by females when feeding on infected hosts or during experimental membrane-feeding. Methods Under standard laboratory conditions, we compared blood meal volumes taken by females of ten sand fly species from four genera: Phlebotomus, Lutzomyia, Migonomyia, and Sergentomyia. The amount of ingested blood was determined using a haemoglobin assay. Additionally, we weighed unfed sand flies to calculate the ratio between body weight and blood meal weight. Results The mean blood meal volume ingested by sand fly females ranged from 0.47 to 1.01 µl. Five species, Phlebotomus papatasi, P. duboscqi, Lutzomyia longipalpis, Sergentomyia minuta, and S. schwetzi, consumed about double the blood meal size compared to Migonomyia migonei. The mean body weight of females ranged from 0.183 mg in S. minuta to 0.369 mg in P. duboscqi. In males, the mean body weight ranged from 0.106 mg in M. migonei to 0.242 mg in P. duboscqi. Males were always lighter than females, with the male-to-female weight ratio ranging from 75% (in Phlebotomus argentipes) to 52% (in Phlebotomus tobbi). Conclusions Females of most species took a blood meal 2.25–3.05 times their body weight. Notably, the relatively tiny females of P. argentipes consumed blood meals 3.34 times their body weight. The highest (Mbl/Mf) ratios were found in both Sergentomyia species studied; females of S. minuta and S. schwetzi took blood meals 4.5–5 times their body weight. This parameter is substantially higher than that reported for mosquitoes and biting midges. Graphical Abstract

Abstract Background Arthropods vector a multitude of human disease-causing organisms, and their geographic ranges are shifting rapidly in response to changing climatic conditions. This is, in turn, altering the landscape of disease risk for human populations that are brought into novel contact with the vectors and the diseases they carry. Sand flies in the genera Lutzomyia and Pintomyia are vectors of serious disease-causing agents such as Leishmania (the etiological agent of leishmaniasis) and may be expanding their range in the face of climate change. Understanding the climatic conditions that vector species both tolerate physiologically and prefer behaviorally is critical to predicting the direction and magnitude of range expansions and the resulting impacts on human health. Temperature and humidity are key factors that determine the geographic extent of many arthropods, including vector species. Methods We characterized the habitat of two species of sand flies, Lutzomyia longipalpis and Pintomyia evansi. Additionally, we studied two behavioral factors of thermal fitness–thermal and humidity preference in two species of sand flies alongside a key aspect of physiological tolerance–desiccation resistance. Results We found that Lu. longipalpis is found at cooler and drier conditions than Pi. evansi. Our results also show significant interspecific differences in both behavioral traits, with Pi. evansi preferring warmer, more humid conditions than Lu. longipalpis. Finally, we found that Lu. longipalpis shows greater tolerance to extreme low humidity, and that this is especially pronounced in males of the species. Conclusions Taken together, our results suggest that temperature and humidity conditions are key aspects of the climatic niche of Lutzomyia and Pintomyia sand flies and underscore the value of integrative studies of climatic tolerance and preference in vector biology. Graphical Abstract

Abstract Canine leishmaniasis is a widespread disease on the American continent, with cases reported from Uruguay to the USA and Canada. While numerous Leishmania spp. have been reported in dogs in this region, Leishmania infantum and Leishmania braziliensis are the most common etiological agents of canine leishmaniasis from a continental perspective. Nonetheless, other species may predominate locally in some countries. The participation of dogs in the transmission cycle of various Leishmania spp. has long been speculated, but evidence indicates that their role as reservoirs of species other than L. infantum is negligible. Various native wildlife (e.g., small rodents, marsupials, sloths, and monkeys) are, in fact, the primary hosts of Leishmania spp. in the Americas. In this review, an updated list of Leishmania spp. infecting dogs in the Americas is presented, along with their distribution and clinical and zoonotic importance Graphical Abstract

Background: The sand fly Nyssomyia neivai is one of the most abundant species in Southern Brazil. It is frequently found in areas that are foci of visceral leishmaniasis in the state of Santa Catarina, caused by Leishmania infantum. In this region, the main vector of L. infantum, Lutzomyia longipalpis, has not been detected. In the absence of L. longipalpis, this study aimed to identify the sand fly fauna and diagnose any potential Leishmania spp. infection in sand flies and in dogs in a region of Southern Brazil that experienced a recent canine visceral leishmaniasis outbreak. Methods: This report includes a survey of the sand fly fauna at the Zoonosis Control Center of the Municipality of Tubarão (Santa Catarina, Brazil). Molecular tests were conducted to investigate Leishmania spp. natural infection in sand flies using polymerase chain reaction (PCR). In positive females, in addition to morphological identification, molecular analysis through DNA barcoding was performed to determine the sand fly species. Additionally, the dogs were tested for the presence of Leishmania spp. using a non-invasive technique for the collection of biological material, to be assessed by PCR. Results: A total of 3419 sand flies, belonging to five genera, were collected. Nyssomyia neivai was the most abundant species (85.8%), followed by Migonemyia migonei (13.3%), Pintomyia fischeri (0.8%), Evandromyia edwardsi (< 0.1%), and species of the genus Brumptomyia. (0.1%). Out of the 509 non-engorged females analyzed by PCR, two (0.4%) carried L. infantum DNA. The naturally infected females were identified as Ny. neivai, in both morphological and molecular analysis. In addition, two out of 47 conjunctival swabs from dogs tested positive for L. infantum, yielding an infection rate of 4.2%. Conclusions: These results confirm the presence of Ny. neivai naturally infected with L. infantum in an area where dogs were also infected by the parasite, suggesting its potential role as a vector in Southern Brazil. [ABSTRACT FROM AUTHOR]

Background: Arthropods vector a multitude of human disease-causing organisms, and their geographic ranges are shifting rapidly in response to changing climatic conditions. This is, in turn, altering the landscape of disease risk for human populations that are brought into novel contact with the vectors and the diseases they carry. Sand flies in the genera Lutzomyia and Pintomyia are vectors of serious disease-causing agents such as Leishmania (the etiological agent of leishmaniasis) and may be expanding their range in the face of climate change. Understanding the climatic conditions that vector species both tolerate physiologically and prefer behaviorally is critical to predicting the direction and magnitude of range expansions and the resulting impacts on human health. Temperature and humidity are key factors that determine the geographic extent of many arthropods, including vector species. Methods: We characterized the habitat of two species of sand flies, Lutzomyia longipalpis and Pintomyia evansi. Additionally, we studied two behavioral factors of thermal fitness–thermal and humidity preference in two species of sand flies alongside a key aspect of physiological tolerance–desiccation resistance. Results: We found that Lu. longipalpis is found at cooler and drier conditions than Pi. evansi. Our results also show significant interspecific differences in both behavioral traits, with Pi. evansi preferring warmer, more humid conditions than Lu. longipalpis. Finally, we found that Lu. longipalpis shows greater tolerance to extreme low humidity, and that this is especially pronounced in males of the species. Conclusions: Taken together, our results suggest that temperature and humidity conditions are key aspects of the climatic niche of Lutzomyia and Pintomyia sand flies and underscore the value of integrative studies of climatic tolerance and preference in vector biology. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that bioclimatic conditions affect the species richness, abundance, and diversity of sand flies in neighboring physiographic regions with endemic transmission of cutaneous leishmaniasis. A sampling program was performed in southeastern Mexico in the High Plateau of Chiapas and the Eastern Mountains physiographic regions, between April 2009 and March 2011. CDC light traps were placed in five randomly selected houses, four CDC traps in four transects in the surrounding vegetation zones, and a modified Magoon trap baited with one protected person was installed at the periphery of the villages at each study site. A total of 12,349 sand flies were identified as species, of which 98.2% were collected in the Eastern Mountains and the rest in the High Plateau of Chiapas. The Eastern Mountains region recorded a significantly higher diversity (H' = 2.04), with a species richness of 27 sand flies species and a higher evenness index (J´ = 0.62) compared to the High Plateau of Chiapas region (H' = 1.02, S = 10, J´ = 0.31). Psychodopygus panamensis (Shannon) (Diptera: Psychodidae) and Pintomyia (Pifanomyia) ovallesi (Ortiz) were the most abundant species in the Eastern Mountains, whereas Lutzomyia (Tricholateralis) cruciata (Coquillett) was most abundant in the High Plateau of Chiapas. We conclude that the differences in species richness, diversity, and abundance of sand flies between these two physiographic regions are due to the bioclimatic effects that in the Eastern Mountains are favorable for the formation of microhabitats due to the warm-warm conditions and the humid-temperate conditions which act as limiting factors in the High Plateau of Chiapas region. In addition, changes in land use due to anthropogenic activities significantly affected the structure of sand fly communities in both regions. [ABSTRACT FROM AUTHOR]

This study investigated the sand fly fauna of the municipality Iguatama, in the Midwest Region of Minas Gerais state, Brazil, including Leishmania infection rates and blood meal sources. Sand flies were collected during four periods over the course of a single year, encompassing both dry and rainy seasons, using CDC light traps placed in peridomiciles where dogs were seropositive for visceral leishmaniasis (VL). A total of 762 sand fly specimens, representing 12 species across seven genera, were collected. Lutzomyia longipalpis was the most abundant species, comprising 57.6% of the collected specimens, followed by Nyssomyia neivai (19.6%) and Nyssomyia whitmani (10.5%). Species richness and diversity varied among collection periods, with the highest diversity observed in January 2019. Molecular analysis detected Leishmania DNA in 12.5% of the sand fly specimens, with Le. infantum being the predominant species. Blood meal analysis revealed feeding on multiple vertebrate species, including humans, rats, dogs, and chickens. The presence of Leishmania DNA in sand flies, and the identification of human blood meals, highlight the potential role of these species in VL transmission. These findings underscore the importance of continued surveillance and control measures to prevent the spread of VL and reduce transmission risk in the region. [ABSTRACT FROM AUTHOR]

Canine leishmaniasis is a widespread disease on the American continent, with cases reported from Uruguay to the USA and Canada. While numerous Leishmania spp. have been reported in dogs in this region, Leishmania infantum and Leishmania braziliensis are the most common etiological agents of canine leishmaniasis from a continental perspective. Nonetheless, other species may predominate locally in some countries. The participation of dogs in the transmission cycle of various Leishmania spp. has long been speculated, but evidence indicates that their role as reservoirs of species other than L. infantum is negligible. Various native wildlife (e.g., small rodents, marsupials, sloths, and monkeys) are, in fact, the primary hosts of Leishmania spp. in the Americas. In this review, an updated list of Leishmania spp. infecting dogs in the Americas is presented, along with their distribution and clinical and zoonotic importance [ABSTRACT FROM AUTHOR]

The present work assessed the experimental susceptibility of Nyssomyia antunesi and Lutzomyia longipalpis to Leishmania (Viannia) lainsoni and L. (V.) lindenbergi. A L. (Leishmania) chagasi–Lu. longipalpis combination was used as a susceptible control. Wild-caught Ny. antunesi and laboratory-bred Lu. longipalpis were membrane-fed on blood with a 5 × 106/mL log-phase promastigote culture suspension and dissected on days 2 and 8 post-blood meal (pbm) for analysis focused on the assessment of parasitoses, as well as placement and promastigote morphotyping. Survival curves were constructed. In all combinations, promastigotes were observed on day 8 pbm. For both Leishmania species, in Lu. longipalpis, the presence of parasites was observed up to the stomodeal valve, while in Ny. antunesi, the presence of parasites was observed up to the cardia. There were no significant differences in parasitosis between L. (V.) lainsoni and L. (V.) lindenbergi in either Ny. antunesi or Lu. longipalpis. Six morphological promastigote forms were distinguished in Giemsa-stained gut smears. The survival curves of all combinations decreased and were affected differently by several Lu. longipalpis–parasite combinations, as well with Lu. longipalpis–uninfected blood. These findings stress Lu. longipalpis as experimentally susceptible to Leishmania spp. and suggest the putative susceptibility of Ny. antunesi to L. (V.) lainsoni and L. (V.) lindenbergi. [ABSTRACT FROM AUTHOR]

The phlebotomine sandfly, Lutzomyia longipalpis, a major vector of the Leishmania parasite, uses terpene pheromones to attract conspecifics for mating. Examination of the L. longipalpis genome revealed a putative terpene synthase (TPS), which--upon heterologous expression in, and purification from, Escherichia coli--yielded a functional enzyme. The TPS, termed LlTPS, converted geranyl diphosphate (GPP) into a mixture of monoterpenes with low efficiency, of which β-ocimene was the major product. (E,E)-farnesyl diphosphate (FPP) principally produced small amounts of (E)-β-farnesene, while (Z,E)-and (Z,Z)-FPP yielded a mixture of bisabolene isomers. None of these mono-and sesquiterpenes are known volatiles of L. longipalpis. Notably, however, when provided with (E,E,E)-geranylgeranyl diphosphate (GGPP), LlTPS gave sobralene as its major product. This diterpene pheromone is released by certain chemotypes of L. longipalpis, in particular those found in the Ceará state of Brazil. Minor diterpene components were also seen as products of the enzyme that matched those seen in a sandfly pheromone extract. [ABSTRACT FROM AUTHOR]

Sandflies are known vectors of leishmaniasis. In the Old World, sandflies are also vectors of viruses while little is known about the capacity of New World insects to transmit viruses to humans. Here, we relate the identification of RNA sequences with homology to rhabdovirus nucleocapsids (NcPs) genes, initially in the Lutzomyia longipalpis LL5 cell lineage, named NcP1.1 and NcP2. The Rhabdoviridae family never retrotranscribes its RNA genome to DNA. The sequences here described were identified in cDNA and DNA from LL-5 cells and in adult insects indicating that they are transcribed endogenous viral elements (EVEs). The presence of NcP1.1 and NcP2 in the L. longipalpis genome was confirmed in silico. In addition to showing the genomic location of NcP1.1 and NcP2, we identified another rhabdoviral insertion named NcP1.2. Analysis of small RNA molecules derived from these sequences showed that NcP1.1 and NcP1.2 present a profile consistent with elements targeted by primary piRNAs, while NcP2 was restricted to the degradation profile. The presence of NcP1.1 and NcP2 was investigated in sandfly populations from South America and the Old World. These EVEs are shared by different sandfly populations in South America while none of the Old World species studied presented the insertions. [ABSTRACT FROM AUTHOR]

In Mexico there are 53 species of phlebotomines (Phlebotominae), of which 35 are present in Chiapas. I report for the first time 13 species for the Montes Azules Biosphere Reserve of Chiapas, Mexico. Six species: Bichromomyia olmeca olmeca (Vargas and Díaz-Nájera 1959), Lutzomyia cruciata (Coquillett 1907), Nyssomyia ylephiletor (Fairchild and Hertig 1952), Pintomyia ovallesi (Ortiz 1952), Psathyromyia shannoni (Dyar 1929), and Psychodopygus panamensis (Shannon 1926), are of medical importance. I document its distribution, which extends to the tropical forest of southeastern Chiapas, and the epidemiological situation of each species. En México existen 53 especies de flebotominos (Phlebotominae), de las cuales 35 están presentes en Chiapas. Reporto por primera vez 13 especies para la Reserva de la Biosfera Montes Azules de Chiapas, México. Seis especies: Bichromomyia olmeca olmeca (Vargas y Díaz-Nájera 1959), Lutzomyia cruciata (Coquillett 1907), Nyssomyia ylephiletor (Fairchild y Hertig 1952), Pintomyia ovallesi (Ortiz 1952), Psathyromyia shannoni (Dyar 1929) y Psychodopygus panamensis (Shannon 1926), son de importancia médica. Documento su distribución, que se extiende hasta el bosque tropical del sureste de Chiapas, y la situación epidemiológica de cada especie. [ABSTRACT FROM AUTHOR]

Background: Understanding aspects related to the physiology and capacity of vectors is essential for effectively controlling vector-borne diseases. The sand fly Lutzomyia longipalpis has great importance in medical entomology for disseminating Leishmania parasites, the causative agent of Leishmaniasis, one of the main neglected diseases listed by the World Health Organization (WHO). In this respect, it is necessary to evaluate the transmission potential of this species and the success of vector control interventions. Near-infrared spectroscopy (NIRS) has been used to estimate the age of mosquitoes in different conditions (laboratory, semi-field, and conservation), taxonomic analysis, and infection detection. However, no studies are using NIRS for sand flies. Methods: In this study, we developed analytic models to estimate the age of L. longipalpis adults under laboratory conditions, identify their copulation state, and evaluate their gonotrophic cycle and diet. Results: Sand flies were classified with an accuracy of 58–82% in 3 age groups and 82–92% when separating them into young (<8 days) or old (>8 days) insects. The classification between mated and non-mated sandflies was 98–100% accurate, while the percentage of hits of females that had already passed the first gonotrophic cycle was only 59%. Conclusions: We consider the age and copula estimation results very promising, as they provide essential aspects of vector capacity assessment, which can be obtained quickly and at a lower cost with NIRS. Key message: Determining adult dipterans sand flies' age and mating status may be necessary for critical assessment of vector control interventions. Near-infrared spectroscopy (NIRS) is a fast, low-cost technique with many advantages compared to the traditional techniques that follow ovarian or cuticle development or pteridine content. In this work, we show for the first time to our knowledge that NIRS may be used for discrimination between young and old sand flies and mated or non-mated adults of both sexes in the Leishmania vector Lutzomyia longipalpis. [ABSTRACT FROM AUTHOR]

In hydroelectric projects, few investigations have been carried out to determine the taxonomic composition of diptera of the family Psychodidae, subfamily Phlebotominae. In this work, a taxonomic inventory of phlebotomine sandflies was conducted in the area of influence of the Ituango hydroelectric power plant, in the department of Antioquia, Colombia. We highlight their medical importance as vectors of the protozoan of the genus Leishmania and update their distribution. Entomological monitoring was carried out in ten municipalities from the western subregion (Santa Fe de Antioquia, Peque, Olaya, Liborina and Sabanalarga) and the northern subregion (the municipalities of Ituango, Briceño, Valdivia, Toledo and San Andrés de Cuerquia). CDC traps and Shannon traps were used for monitoring. For taxonomic identification, the keys of Young and Duncan and Galati were used. A total of 7993 phlebotomine sandflies were collected, distributed in 39 species according to Galati, highlighting six species considered vectors of Leishmania spp. that causes cutaneous leishmaniasis, which are: Lutzomyia (Trl.) gomezi, Lu. (Hel.) hartmanni, Psychodopygus panamensis, Pintomyia (Pif.) columbiana, Nyssomyia trapidoi and Ny. yuilli yuilli. We conclude that the sampling area is endemic for leishmaniasis due to the presence of vectors transmitting this parasite. The inventory on the distribution of phlebotomine sandflies will serve as a basis for further studies that allow the implementation of surveillance and control strategies. [ABSTRACT FROM AUTHOR]

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ABSTRACT This research aimed to carry out an epidemiological investigation of dogs with canine leishmaniasis in an area of Rio Grande do Sul with no history of notification of the disease. Leishmaniasis is considered an endemic zoonosis in different countries. In Brazil, it occurs mainly in the Southeast and Midwest regions, having drastically increased the number of notifications in recent years. In the state of Rio Grande do Sul, there are reports of the disease in the metropolitan region of Porto Alegre and in the border region in the west of the state, as well as in the central region. The investigation was conducted in 100 dogs from the municipalities of Frederico Westphalen and region. Whole blood was collected for immunochromatographic testing (TR DPP® Canine Visceral Leishmaniasis) and lymph node aspiration. Positives were confirmed by ELISA test and indirect immunofluorescence test with total dilution or immunohistochemistry after skin biopsy. Two animals were diagnosed with visceral leishmaniasis, considered the first reported cases of the disease in the canine population in the region. Therefore, it becomes necessary to research and control the potential presence of sandflies in the area. There is a hypothesis that the animals were contaminated in other regions of the country, remaining as a reservoir until the moment of diagnosis.

Methods, results, and discussion: In this study, we investigated the expression of Lutzomyia longipalpis genes involved in regulating the Toll pathway under parasitic infection. Leishmania infantum infection upregulated the expression of two L. longipalpis genes coding for the putative repressors cactus and protein tyrosine phosphatase SHP. These findings suggest that the parasite can modulate the vectors' immune response. In mammalian infections, the Leishmania surface glycoprotein GP63 is one of the inducers of host immune depression, and one of the known effectors is SHP. In L. longipalpis we found a similar effect: a genetically modified strain of Leishmania amazonensis over-expressing the metalloprotease GP63 induced a higher expression of the sand fly SHP indicating that the L. longipalpis SHP and parasite GP63 increased expressions are connected. Immuno-stained microscopy of L. longipalpis LL5 embryonic cells cultured with Leishmania strains or parasite conditioned medium showed cells internalization of parasite GP63. A similar internalization of GP63 was observed in the sand fly gut tissue after feeding on parasites, parasite exosomes, or parasite conditioned medium, indicating that GP63 can travel through cells in vitro or in vivo. When the sand fly SHP gene was silenced by RNAi and females infected by L. infantum, parasite loads decreased in the early phase of infection as expected, although no significant differences were seen in late infections of the stomodeal valve. Conclusions: Our findings show the possible role of a pathway repressor involved in regulating the L. longipalpis immune response during Leishmania infections inside the insect. In addition, they point out a conserved immunosuppressive effect of GP63 between mammals and sand flies in the early stage of parasite infection. [ABSTRACT FROM AUTHOR]

Abstract Background Blood-sucking phlebotomine sand flies are vectors of the protozoan parasites Leishmania spp. Although the intestinal microbiota is involved in a wide range of biological and physiological processes and has the potential to alter vector competence, little is known about the factors that modify the gut microbiota composition of sand flies. As a key step toward addressing this issue, we investigated the impact of host species on the gut bacterial composition in Phlebotomus and Lutzomyia sand flies reared under the same conditions. Methods Bacterial 16S rRNA gene amplification and Illumina MiSeq sequencing were used to characterize the overall bacterial composition of three laboratory-reared sandflies: Phlebotomus papatasi, Ph. duboscqi, and Lutzomyia longipalpis. Results Our results showed that the larvae of the three sand fly species harbored almost the same microbes but had different relative abundances. Adult Ph. papatasi and Ph. duboscqi revealed similar microbiome compositions, which were distinct from that of adult Lu. longipalpis. Furthermore, we showed that Ph. papatasi and Ph. duboscqi are hosts for different bacterial genera. The experiment was repeated twice to improve accuracy and increase reliability of the data, and the same results were obtained even when a distinct composition of the microbiome among the same species was identified probably because of the use of different larvae food batch. Conclusions The present study provides key insights into the role of host species in the gut microbial content of different sand fly species reared under the same conditions, which may influence their susceptibility to Leishmania infection. Graphical Abstract

Background: Blood-sucking phlebotomine sand flies are vectors of the protozoan parasites Leishmania spp. Although the intestinal microbiota is involved in a wide range of biological and physiological processes and has the potential to alter vector competence, little is known about the factors that modify the gut microbiota composition of sand flies. As a key step toward addressing this issue, we investigated the impact of host species on the gut bacterial composition in Phlebotomus and Lutzomyia sand flies reared under the same conditions. Methods: Bacterial 16S rRNA gene amplification and Illumina MiSeq sequencing were used to characterize the overall bacterial composition of three laboratory-reared sandflies: Phlebotomus papatasi, Ph. duboscqi, and Lutzomyia longipalpis. Results: Our results showed that the larvae of the three sand fly species harbored almost the same microbes but had different relative abundances. Adult Ph. papatasi and Ph. duboscqi revealed similar microbiome compositions, which were distinct from that of adult Lu. longipalpis. Furthermore, we showed that Ph. papatasi and Ph. duboscqi are hosts for different bacterial genera. The experiment was repeated twice to improve accuracy and increase reliability of the data, and the same results were obtained even when a distinct composition of the microbiome among the same species was identified probably because of the use of different larvae food batch. Conclusions: The present study provides key insights into the role of host species in the gut microbial content of different sand fly species reared under the same conditions, which may influence their susceptibility to Leishmania infection. [ABSTRACT FROM AUTHOR]

In the Americas, the sandfly Lutzomyia longipalpis is the main vector of the parasitic protozoa Leishmania infantum, the etiological agent of visceral leishmaniasis (VL). The Lu. longipalpis species complex is currently discontinuously distributed across the Neotropical region, from Mexico to the north of Argentina and Uruguay. During its continental spreading, it must have adapted to several biomes and temperature amplitudes, when founder events should have contributed to the high genetic divergence and geographical structure currently observed, reinforcing the speciation process. The first report of Lu. longipalpis in Uruguay was in 2010, calling the attention of Public Health authorities. Five years later, the parasite Le. infantum was recorded and in 2015 the first case of VL in canids was reported. Hitherto seven human cases by VL have been reported in Uruguay. Here, we publish the first DNA sequences from the mitochondrial genes ND4 and CYTB of Lu. longipalpis collected in Uruguay, and we used these molecular markers to investigate their genetic variability and population structure. We described four new ND4 haplotypes in a total of 98 (4/98) and one CYTB in a total of 77 (1/77). As expected, we were able to establish that the Lu. longipalpis collected in two localities (i.e. Salto and Bella Unión) from the north of Uruguay are closely related to the populations from neighbouring countries. We also propose that the possible route for the vector arrival to the region may have been through vegetation and forest corridors of the Uruguay River system, as well as it may have benefited from landscape modifications generated by commercial forestation. The ecological‐scale processes shaping Lu. longipalpis populations, the identification of genetically homogeneous groups and the gene flow among them must be carefully investigated by using highly sensible molecular markers (i.e. genome wide SNPs) since it will help to the understanding of VL transmission and contribute to the planification of public policies on its control. [ABSTRACT FROM AUTHOR]

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. Author summary: Sandflies are insects that actively participate in the transmission cycles of leishmaniasis and other diseases, and these invertebrate vectors are frequently found in areas with hot and humid climates. However, in addition to the climate, there are several factors that contribute to the occurrence of sandfly vectors, such as, the vegetation type, altitude, and land use and cover. Understanding which environmental variables are important for the presence of sandflies can help us to understand how these insects are distributed and overall, how this affects the transmission of the etiological agents of leishmaniasis. In this study, we performed a set of ecological models where environmental and climatic variables were combined in multiple scales and correlated with the presence of two sandflies species, Lutzomyia longipalpis and Nyssomyia whitmani, vectors of parasites causing visceral and cutaneous leishmaniasis, respectively. We then combined this information with human disease data to assess potential risk areas in the state of Piauí, northeast Brazil. The resulting maps showed that municipalities of the central-north region of the state have favorable environment for the occurrence of these vectors in addition to higher incidence of leishmaniasis in humans. We thus recommend that control activities should be focused on this region of the state. [ABSTRACT FROM AUTHOR]

Phlebotomine sand flies are dipterans of relevance due to their role as vectors of several pathogens worldwide. Bacteria in the gut of sand flies possibly affect their vectorial capacity and competence to transmit parasites. A retrospective study was performed in sand fly specimens that had previously been collected in four localities of the state of Chiapas during the period 2009–2011 to detect Wolbachia and Bartonella and their possible coinfection with Leishmania. For the molecular detection of bacteria, we used primers and conditions that had previously been reported. A total of 531 sand fly specimens of 10 species were analyzed. Four Wolbachia strains were detected in five sand fly species, showing a prevalence of 8.6%. All the Wolbachia strains had previously been reported in other taxa. In one sand fly species, we also detected a new lineage of Bartonella evidenced by a phylogenetic analysis. No sand fly specimens showed coinfections of these bacteria and Leishmania. The bacteria found in the phlebotomine sand flies are possibly transmitted by plant-mediated horizontal transmission and during blood meal feeding. [ABSTRACT FROM AUTHOR]

Background:Bartonella ancashensis is a recently described Bartonella species endemic to Peru, where it causes verruga peruana in humans. While the arthropod vector of B. ancashensis transmission is unknown, human coinfections with Bartonella bacilliformis suggest that phlebotomine sand flies are a vector. Materials and Methods: To address the hypothesis that sand flies are involved in the bacterium's transmission, Lutzomyia longipalpis sand flies were used as an infection model, together with green fluorescent protein-expressing B. ancashensis. Results: Results showed that bacterial infections were clearly established, limited to the anterior midgut of the female fly, and maintained for roughly 7 days. At 3–7 days postinfection, a prominent microcolony of aggregated bacteria was observed in the anterior midgut, immediately distal to the stomodeal valve of the esophagus. In contrast, eggs, diuretic fluid, feces, and other tissues were not infected. Conclusion: These results suggest that certain sand fly species within the endemic zone for B. ancashensis may play a role in the bacterium's maintenance and possibly in its transmission to humans. [ABSTRACT FROM AUTHOR]

Phlebotominae sand flies are the main vectors of several species of Leishmania parasites that are the etiological agents of leishmaniasis. The disease is endemic to southeastern Mexico, and many studies focused on the area. Cases of leishmaniasis also occur in other Mexican states such as Coahuila, Nuevo León, and Tamaulipas in the northeastern region bordering the United States of America (USA). Cutaneous leishmaniasis was reported intermittently in the State of Nuevo León through the years. Few records of sand fly species exist for the State of Nuevo León, and many municipalities have not been sampled despite potential importance of the disease at certain localities. The main objective of the work was to trap sand flies at the Municipality of General Zuazua, Nuevo León where urbanization occurred rapidly in recent years. A semi-urban location was selected to catch sand fly species using CDC light traps from 6 August through 26 September 2020. In total, 137 specimens in four genera and five species were collected during nine sampling events. Lutzomyia diabolica (Hall, 1936) was dominant at 90.5% of the total collected. Abundance of sand fly species peaked at Sampling Event 5 (34.3%) and differed significantly between sampling events and trap locations at six sites. Using Taylor´s power law, spatial distribution of sand flies was aggregated at the study site. Environmental variables such as air temperature, soil temperature, relative humidity, dew point, and wind speed were not significantly related to abundance of sand flies. The five sand fly species in the study -- Dampfomyia anthophora (Addis, 1945), Micropygomyia apache (Young and Perkins, 1984), Micropygomyia californica (Fairchild and Hertig, 1957), Psathyromyia texana (Dampf, 1938), and Lutzomyia diabolica were new records for the Municipality of General Zuazua, Nuevo León. Although the taxonomic status of M. californica is debatable, the species was recorded for the first time in México. The five species can be added to previous records, for a total of 10 species in the State of Nuevo León. Brief discussion of medical importance of each sand fly species to transmit Leishmania spp. is provided for the region. [ABSTRACT FROM AUTHOR]

Sandfly species (Diptera: Psychodidae) are suspected or proven vectors of Leishmania spp. in the American region. Understanding niche conservatism (NC) in insect vectors allows an understanding of constraints on adaptive responses, and thus implications for disease ecology. Therefore, in this study, the authors evaluated NC in three vector species of leishmaniasis (Lutzomyia gomezi, Psathyromyia shannoni and Pintomyia ovallesi) in Central and South America. For this, the authors performed niche identity and similarity testing through paired comparisons in ENMTools and niche overlap in Niche Analyst. The authors found that species niches were more similar to each other than if the points had been randomly extracted, and they also found extensive similarity between Pa. shannoni and Lu. gomezi niches and in Pa. shannoni niches over different timescales. The authors suggest Pa. shannoni as a priority species due to fundamental niche similarity with phylogenetically related species and also its extensive evolutionary history and ecological plasticity that could affect the emergence and resurgence of leishmaniasis in areas endemic by this vector. [ABSTRACT FROM AUTHOR]

We previously showed that L. (Leishmania) amazonensis promastigotes and amastigotes of the PH8 strain generated larger lesions in mice than LV79, and that lesion-derived amastigotes from the two strains differ in their proteomes. We recently reported that PH8 promastigotes are more phagocytized by macrophages. Promastigotes' membrane-enriched proteomes showed several differences, and samples of each strain clustered based on proteomes. In this paper, we show phenotypic differences between PH8 and LV79 promastigotes that may explain the higher virulence of PH8. We compared in vitro macrophage infections by day 4 (early) and day 6 (late stationary phase) cultures, resistance to complement, and LPG characteristics. PH8 promastigotes showed a higher infectivity and were more resistant to murine complement. LPG was different between the strains, which may influence the interaction with macrophages and survival to complement. We compared the infection of the permissive vector Lutzomyia longipalpis. PH8 was more abundant in the vector's gut 72 h after feeding, which is a moment where blood digestion is finished and the parasites are exposed to the gut environment. Our results indicate that PH8 promastigotes are more infective, more resistant to complement, and infect the permissive vector more efficiently. These data suggest that PH8 is probably better adapted to the sand fly and more prone to survive in the vertebrate host. [ABSTRACT FROM AUTHOR]

Leishmaniasis is a zoonosis acquired by the bite of a female sandfly, which introduces leishmania promastigotes into the bloodstream. The clinical manifestations are determined by the host's immunity, which ranges from a localized to a disseminated form. To date, several genera of sandflies have been identified, with Phlebotomus (Old World) and Lutzomyia (New World) being the most important for the transmission of leishmania spp. Diagnosis requires demonstration ofthe parasite in a sample obtained from a suspicious lesion using methods such as PCR, Giemsa stain, culture, among others. The management of leishmaniasis depends on the presentation and underlying cause. A case of cutaneous leishmaniasis associated with kidney transplant is presented, highlighting its clinical aspects, manifestations, histopathological findings, outcome and treatment. [ABSTRACT FROM AUTHOR]

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Copyright of Ciência & Trópico (03042685) is the property of Fundacao Joaquim Nabuco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: Leishmaniases are a group of vector-borne zoonotic diseases of public health relevance within the tropical and subtropical regions of the world. The state of Yucatan is a vulnerable and receptive area to localized cutaneous leishmaniasis (LCL) due to its proximity to the high-transmission endemic states of Campeche and Quintana Roo. Autochthonous cases of LCL caused by Leishmania (Leishmania) mexicana have been documented in the state, showing a geographical expansion of the disease. Materials and Methods: Using CO2-supplemented Centers for Disease Control and Prevention light traps and Shannon traps, we captured anthropophilic sandflies in the surroundings of a locality with recent records of autochthonous cases of LCL. Sandflies carrying Leishmania DNA were evidenced using PCR. Results: A total of 140 Phlebotominae (Diptera: Psychodidae) females of four species were captured: Lutzomyia (Tricholateralis) cruciata (Coquillett), Psathyromyia (Psathyromyia) shannoni (Dyar), Lutzomyia (Lutzomyia) longipalpis (Lutz and Neiva), and Dampfomyia (Coromyia) deleoni (Fairchild and Hertig). Molecular results showed that 6.1% (95% confidence interval [CI] = 2.3–12.9%) of Lu. cruciata and 43.8% (95% CI = 19.8–70.1%) of Pa. shannoni showed evidence of carrying L. (L.) mexicana DNA. Conclusion: We provide evidence of anthropophilic sandflies carrying L. mexicana DNA in a municipality with recorded autochthonous cases of LCL caused by this parasite species in the state of Yucatan, suggesting the emergence of new focus of LCL in Mexico. [ABSTRACT FROM AUTHOR]

Visceral leishmaniasis remains a serious public health issue, and Brazil was among the seven countries with the highest prevalence of this disease worldwide. The measures to control this disease are not easily developed, and the improvement of its diagnosis, surveillance, and control is still needed. This study aimed to carry out the polymerase chain reaction (PCR) diagnosis of Leishmania infantum in vector samples in some municipalities of the State of São Paulo, which included two municipalities with human disease transmission and two with dog transmission only. Vectors were collected in traps with luminous bait. Next, they were killed at −4 °C and kept in 70% alcohol. Groups of ten female insects (pools) were mashed on cation exchange paper (fine cellulose phosphate with 18 µEq/cm² ionic exchange capacity) for DNA extraction. The PCR was carried out to identify the natural infection of the Leishmania genus in female Lutzomyia longipalpis (Lu. Longipalpis). Out of the 3,880 Lu. longipalpis phlebotomines, 1060 were female and 2820 were male (3:1). The method used to extract the DNA in pools of ten phlebotomines and the PCR resulted in sensitivity, specificity, practicality, and faster analyses when compared to the individual analysis method. The procedure described can be used on a large scale in the leishmaniasis epidemiological surveillance, enabling a higher number of analyses and the optimization of human resources because the traditional diagnostic method is carried out via desiccation of the insect digestive system and microscopic examination, which is time-demanding and there is the need of manual skills. [ABSTRACT FROM AUTHOR]

Sand flies are hematophagous dipterans and are considered vectors of the parasites belonging to the genus Leishmania, which can infect mammals, including humans, and subsequently cause leishmaniasis. Rio Grande do Sul State (RS), southern Brazil, was considered free of this disease for the last few decades. However, several autochthonous cases of visceral leishmaniasis (VL) have been recorded in different municipalities in recent years. Since 2017, cases of canine visceral leishmaniasis (CVL) have been reported in the municipality of Santa Maria, located in the central region of RS. In 2021, two cases of human VL were confirmed in the city, resulting in one death. To capture the possible vectors involved in the disease transmission cycle, Centers for Disease Control (CDC) modified light traps were installed in the peridomestic residential areas. These points were situated in two city districts where cases of CVL had been reported from January 2021 to January 2022. In the 41 sample collections of sand flies, 9 specimens of Lutzomyia longipalpis were identified, confirming the municipality as an area of VL transmission, according to Brazilian sanitary standards. The spread of Leishmania spp. has been occurring efficiently, resulting in a negative impact on the One Health. This study reports the first detection of L. longipalpis in the central region of RS. [ABSTRACT FROM AUTHOR]

• The part of the insect used as a sample has an impact on the peptide/protein profile • Biological variables altered the profiles, generating identifiable diagnostic ions • When identifying sand flies with MALDI-TOF, biological factors must be considered • In the future, it will be possible to use MALDI-TOF to identify wild sand flies Sand flies are vectors of great public health importance, since they constitute a group of hematophagous insects responsible for etiological agents transmission of zoonotic diseases such a visceral leishmaniasis. In face of the expansion of these diseases, efficient control strategies are needed which depend on comprehending the sand fly eco-epidemiology. In this regard, MALDI-TOF mass spectrometry has been used for bacteria, fungi and yeast detection studies through peptide/protein profiles. However, little is known about interference of biological factors associated with vector ecology, such as blood meal preferences and even sand fly age on the peptide/protein profiles. Thus, the present study aimed to evaluate the differences in peptide/protein profiles of the sand fly Lutzomyia longipalpis , by means of MALDI-TOF, due to the sand fly's age, sex, blood meal source and Leishmania infantum infection. Sample preparation was made removing both head and last abdomen segments keeping the thorax, its appendices and the rest of the abdomen. Five specimens per pool were used to obtain peptide/protein extract of which 1 μL solution was deposited over 1 μL MALDI matrix dried. Characteristic spectra were analyzed using principal coordinate analysis as well as indicator species analysis to discriminate differences in sand flies's peptide/protein profile by sex, age, blood meal source and L. infantum infection. The results show that the evaluated variables produced distinct peptide/protein profiles, demonstrated by the identification of specific diagnostic ions. It was found that the interference of biological factors should be taken into account when using the MALDI-TOF analysis of sand fly species identification and eco-epidemiological applications in field studies. Based on our results, we believe that it is possible to identify infected specimens and the source of blood meal in a collection of wild sand flies, serving to measure infectivity and understand the dynamics of the vector's transmission chain. Our results may be useful for epidemiological studies that look at the ecology of sand flies and leishmaniasis, as well as for raising awareness of biological characteristics' impact on peptide/protein profiles in sand fly species identification. Experimental study design to evaluate the biological effects of age, blood feeding and Leishmania infantum infection in the sand fly species Lutzomyia longipalpis. [Display omitted] [ABSTRACT FROM AUTHOR]

Phlebotomine sand flies are critical vectors of Leishmania parasites, impacting public health significantly. This study focused on assessing the diversity of sand flies in a rural area of El Carmen de Bolívar Municipality, northern Colombia, employing rarefaction curves and Hill numbers to understand potential vector communities and inform environmental management. From January 2018 to April 2019 (five samplings), sand flies were collected using CDC light traps with blue LED in domestic/peridomestic/sylvatic ecotopes, identifying species per Young and Duncan (1994) and Galati (2003). Hill numbers provided diversity estimates across samples, while Principal Component Analysis correlated with environmental factors with phlebotomine species presence and abundance. 8,784 phlebotomine individuals were collected; 56.4 % females and 43.6% males (ratio 3:2). These individuals belonged to eight species: Pintomyia evansi, Psychodopygus panamensis, Lutzomyia gomezi, Micropygomyia cayennensis, Evandromyia dubitans, Psathyromyia aclydifera, Pintomyia serrana , and Pintomyia rangeliana ; with Pi. evansi being the most abundant species (74.39 %; 6,530 exemplars). The ANOVA showed no significant differences between phlebotomine sand flies abundances across ecotopes (p = 0.018). Species of epidemiological relevance as Pi. evansi and Lu. gomezi not show a positive correlation with environmental variables evaluated, only Ps. panamensis was positively correlated with precipitation. However, the study emphasizes the need for a continuous sand fly monitoring and research to enhance leishmaniasis control strategies, highlighting the necessity to expand knowledge on phlebotomine diversity and environmental interactions to understand vector ecology and disease dynamics better. [ABSTRACT FROM AUTHOR]

• Geographical distribution of 22 sand fly species in leishmaniasis endemic areas of Mexico is updated, as well as altitudinal and bioclimatic patterns of their distribution are identified. • We recorded sand fly species for the first time in the states of Morelos (3); Oaxaca (7) and Tabasco (1), Mexico. • The 82 % of sand fly specimens collected are distributed in areas with altitudinal ranges between 1 and 540 m.a.s.l. • In a PCA of Worldclim variables, 72 % of variation of sand fly species distribution is correlated with temperature of coldest month and precipitation of wettest quarter. • Sand fly species Psathyromyia shannoni, Psathyromyia carpenteri, Lutzomyia cruciata , and Lutzomyia longipalpis displayed the greatest variability regarding altitudinal ranges and climatic variables. This study updates knowledge on historical geographic distribution of sand fly species through identifying altitudinal and bioclimatic patterns in leishmaniasis endemic areas in Mexico. We analyze and identify sand fly specimens obtained through national efforts by the Instituto de Diagnóstico y Referencia Epidemiológicos (InDRE, Mexico), collected between 1995 and 2001, 2008–2012, and 2017–2023, and add bibliographic information (427 additional records). After a principal components analysis of WorldClim variables and altitudinal ranges, variables that better explain the distribution of sand fly species were chosen (BIO6, BIO12, and BIO16, explaining 72 % of variation). A total of 1,187 specimens of 22 species were retrieved from eight states, providing 29 new municipalities and 48 new localities, being Lutzomyia cruciata, Micropygomyia chiapanensis , and Psathyromyia shannoni the most common species. We presented new historical records of distribution for sand fly species from Morelos (3), Oaxaca (7) and Tabasco (1). The 82.7 % of sand fly species analyzed were distributed in areas with altitudinal ranges below 420 m. The anthropophilic species Psathyromyia shannoni , and Lutzomyia cruciata showed the greatest variability regarding altitudinal range, and climatic preferences, while several wild species showed abiotic preferences. It is likely that the effect of urbanization and climate change generate new beneficial biotopes for the proliferation of the vector sand fly species. Complementary studies that consider seasonality, vegetation types, and change in land use could provide new information to better understand the spread of vector-borne diseases. This is the first country-level effort to update knowledge on geographical distribution of sand fly species in leishmaniasis endemic areas in Mexico, as well as to identify altitudinal and bioclimatic patterns of their distribution. [Display omitted] [ABSTRACT FROM AUTHOR]

• Effect of L. a mazonensis infection was evaluated. • Attractiveness of uninfected and infected Hasmters was evaluated to Lu. longipalpis. • Behavioral trials did not show any influence of infection on the blood meal rates. • Analysis of VOCs profiles from infected host also did not show differences. Lutzomyia longipalpis is the primary vector of Leishmania infantum in the Americas and a permissive vector for Leishmania amazonensis. Previous studies showed that Leishmania infantum -infected hosts can release different volatile organic compounds (VOCs) compared with uninfected hosts, presenting a higher attractiveness to vectors. In this study, we aimed to evaluate a possible effect of L. amazonensis infection of golden hamsters in three parameters: attractiveness to Lu. longipalpis females; blood volume ingested by sand fly females; and VOCs released by the animals.. Attractiveness was measured indirectly by the number of Lu. longipalpis females that blood fed in each L. amazonensis -infected and uninfected animal. For VOCs extraction, solid phase micro extraction fibers were used, which were analyzed by gas chromatography-mass spectrometry. Behavioral trials did not show any effect of L. amazonensis infection on the attraction of sand flies nor difference on blood meal rates of Lu. longipalpis fed in both goups of hamsters. Additionally, there was no difference between the VOCs profiles of L. amazonensis -infected or uninfected hamsters. [Display omitted] [ABSTRACT FROM AUTHOR]

The Leishmania infantum (synonym, Leishmania chagasi) causes life‐threatening infection, namely canine leishmaniosis (CanL), which is a chronic zoonosis prevalent in various countries and spread by the bite of the infected Lutzomyia female sandfly in South America. The objective of the study was to assess the effectiveness of a polymer matrix collar containing made up of 10% imidacloprid and 4.5% flumethrin for the prevention of canine leishmaniosis from the hyperendemic region falling under Araçatuba municipality (Brazil). The research included a total of 146 dogs chosen from 75 households. Test were initiated via physical examination; weighing and biological sample collection (blood, popliteal lymph node and conjunctival swab) of these dogs were done in March 2018 (Day 0; GA, control = 69, GB, treated = 77) to initiate laboratory tests. Post‐inclusion, the animals were monitored on the 120th, 240th, 360th and 480th days, respectively. The usage of collars continued between 0 and 480 days before being substituted in second (D240) and fourth (D480) follow‐up visits. On the whole, 25 dogs in GA (36.2%) and three in GB (3.9%) were found positive for L. infantum infection in a minimum of one diagnostic test used in the research. Therefore, the average collar effectiveness for protection from L. infantum infection was 89.2% (p <.01). In the last follow‐up, the average incidence density rate for GA was 30.7%, whereas for GB, it was 2.9%. The imidacloprid/flumethrin collars evaluated in the research were found to be safe and extremely efficient for the prevention of L. infantum infection through Lutzomyia species among the large population of dogs in highly prone endemic regions. This is a dependable and efficient technique aimed at reducing the occurrence and propagation of this illness among the population of canines, which would eventually reduce the human‐health‐related hazards. In Brazil, Lutzomyia spp. is a leading vector of the infection; thus, the collar can be used to limit infection in dogs and humans. [ABSTRACT FROM AUTHOR]

The use of repellents is considered an alternative against biting insects, including Lutzomyia longipalpis (Diptera: Psychodidae), the main vector of the protozoan Leishmania infantum, visceral leishmaniasis's (VL) etiologic agent in the Americas. This study aimed to evaluate the repellent efficacy of icaridin nanostructured solution applied on cotton knitting fabric against L. longipalpis. Arm-in-cage tests were performed in eight volunteers at different concentrations (5%, 10%, 25%, and 50%), using L. longipalpis (n = 30). The bioassay was performed in 1, 24, 48, 72, 96, 120, and 144 h after impregnation and one test after washing the fabrics with icaridin. The total repellency rate (%R) > 95% was used as a reference to define a minimum effective concentration (MEC). The results revealed that the insects' landing mean decreased significantly in different icaridin concentrations, compared with the control tests (p < 0.05) and the 25% and 50% concentrations compared to lower concentration (5%) (p < 0.05). The higher concentrations (25% and 50%) provided longer complete protection times (CPTs) with 120 and 144 h of protection, respectively and the %R of 100% for 72 and 96 h after impregnation, respectively. The 25% was the MEC (%R Total = 98.18%). Our results indicate, for the first time, that icaridin nanostructured solution applied on cotton knitting fabric proved to be an efficient repellent against L. longipalpis with the presence of repellent action even after washing. The concentration of 25% showed better efficiency and may become an efficient method for L. longipalpis biting control. [ABSTRACT FROM AUTHOR]

The estimation of changes in the diversity and composition of insect communities in transmission areas belonging to different life zones, can indicate differential patterns in transmission and associated reservoir fauna, as well as different epidemiological risk scenarios. An example is leishmaniasis, a parasitosis related to the presence of phlebotomine sandflies of the Lutzomyia genus, which in Córdoba (Colombia) presents transmission areas for cutaneous and visceral forms of leishmaniasis, framed in different life zones - Holdridge (Bs-T, Bh-T, among others). The present study aims to estimate the diversity of entomological inventories carried out in different areas with presence of potential leishmaniasis vectors, in 17 localities of ten municipalities of the department of Córdoba, between May 2015 and November 2016. A total of 1695 phlebotomine sandflies represented in 13 species of the genus Lutzomyia were collected. The most abundant species for the department of Córdoba are Lutzomyia evansi and Lutzomyia gomezi, with 30.44 % and 29.62 %, respectively. The presence of Lutzomyia trapidoi is reported for the first time for the territory of Córdoba. With this study, the knowledge of the diversity of the genus Lutzomyia in terms of abundance distribution, true diversities and species composition in active zones of the department of Córdoba is expanded. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the diversity of phlebotomine sandflies (Diptera: Psychodidae) in the peri-urban area of Montería, Córdoba, Colombia. The specimens were collected in four locations around Monteria with CDC traps and manual aspirators between February and June 2018, and they were fragmented and clarified with lactophenol, for later identification by means of specialized taxonomic keys. The diversity was estimated with the Shannon-Wiener index, localities were compared using the distance of Bray-Curtis and the richness was quantified with the Chao 2 and Jacknife 2 indices. Six species were identified: Micropygomyia cayennensis, Lutzomyia gomezi, Pintomyia rangeliana, Micropygomyia micropyga, Psathyromyia shannoni, and Pintomyia evansi. The sampling sites were similar in terms of diversity. The peri-urban area of Monteria is inhabited by generalist species of dipterans of the Psychodidae family that constitute an epidemiological risk. The species richness was affected by the characteristics of the species found. [ABSTRACT FROM AUTHOR]

Parasites of the genus Porcisia, together with the genus Endotrypanum, form a sister clade to the species-rich and medically important genus Leishmania. Both Porcisia species, P. hertigi and P. deanei, are dixenous parasites of Neotropical porcupines. Almost 50 years after their first discovery, knowledge of their life cycle remains poor and their insect vectors are unknown. Because competent vectors of their closest phylogenetic relatives, genera Endotrypanum and Leishmania, are phlebotomine sand flies (Diptera: Psychodidae) and/or biting midges (Diptera: Ceratopogonidae), we examined here the potential of both sand flies and biting midges to transmit Porcisia parasites. The insects (Lutzomyia longipalpis, L. migonei and Culicoides sonorensis) were exposed to parasites through the chicken skin membrane and dissected at various time intervals post bloodmeal. Potentially infected females were also allowed to feed on the ears of anaesthetized BALB/c mice and the presence of parasite DNA was subsequently confirmed in the mice by PCR. Porcisia hertigi did not survive defecation in L. longipalpis or L. migonei, suggesting that these sand fly species are unlikely to serve as natural vectors of this parasite. Similarly, P. hertigi infections were lost in Culicoides midges. In contrast, mature P. deanei infections developed in 51-61% of L. longipalpis females, 7.3% of L. migonei females and 7.7% of Culicoides sonorensis females. In all three vector species, P. deanei colonized predominantly Malpighian tubules and produced metacyclic infective forms. Transmission of P. daenei to BALB/c mice was demonstrated via the prediuresis of L. longipalpis females. This mode of transmission, as well the colonization of Malpighian tubules as the dominant tissue of the vector, is unique among trypanosomatids. In conclusion, we demonstrated the vector competence of L. longipalpis for P. deanei but not for P. hertigi, and further studies are needed to evaluate competence of other Neotropical vectors for these neglected parasites. [ABSTRACT FROM AUTHOR]

The sand fly Lutzomyia longipalpis is the main vector of Leishmania infantum in the Americas. Female sand flies ingest sugar‐rich solutions and blood, which are digested in the midgut. Digestion of nutrients is an essential function performed by digestive enzymes, which require appropriate physiological conditions. One of the main aspects that influence enzymatic activity is the gut pH, which must be tightly controlled. Considering second messengers are frequently involved in the coordination of tightly regulated physiological events, we investigated if the second messenger cAMP would participate in the process of alkalinization in the abdominal midgut of female L. longipalpis. In midguts containing the indicator dye bromothymol‐blue, cAMP stimulated the alkalinization of the midgut lumen. Through another technique based on the use of fluorescein as a pH indicator, we propose that cAMP is involved in the alkalinization of the midgut by activating HCO3– transport from the enterocyte's cytoplasm to the lumen. The results strongly suggested that the carrier responsible for this process would be a HCO3−/Cl− antiporter located in the enterocytes' apical membrane. Hematophagy promotes the release of alkalinizing hormones in the hemolymph; however, when the enzyme adenylyl cyclase, responsible for cAMP production, was inhibited, we observed that the hemolymph from blood‐fed L. longipalpis' females did not stimulate midgut alkalinization. This result indicated that hormone‐stimulated alkalinization is mediated by cAMP. In the present study, we provide evidences that cAMP has a key role in the control of intestinal pH. [ABSTRACT FROM AUTHOR]

Leishmaniasis control often relies upon insecticidal control of phlebotomine sandfly vector populations. Such methods are vulnerable to the evolution of insecticide resistance via a range of molecular mechanisms. There is evidence that two major resistance mechanisms, target site insensitivity and metabolic resistance, have evolved in some sandfly populations and further genetic characterization of resistance would be useful to understand and combat it. To facilitate the study of the mechanisms of metabolic resistance, here we improved the annotation and characterized a major detoxification gene family, the glutathione‐s‐transferases (GST), in the genomes of two sand fly species: Phlebotomus papatasi and Lutzomyia longipalpis. The compositions of the GST gene family differ markedly from those of Aedes and Anopheles mosquitoes. Most strikingly, the xi (X) class of GSTs appears to have expanded in both sand fly genomes. Our results provide a basis for further studies of metabolic resistance mechanisms in these important disease vector species. [ABSTRACT FROM AUTHOR]

Leishmaniasis is a neglected tropical disease that continues to pose a serious public health problem. Albeit dogs have long been held as the major reservoirs of Leishmania infantum, the involvement of domestic cats in the zoonotic cycle of visceral leishmaniasis has gained prominence. Here, 240 cats were evaluated by clinical signs and haematological/biochemical changes compatible with leishmaniasis and were diagnosed by serological, molecular, and parasitological techniques. Thus, four cats naturally infected by L. infantum were submitted to xenodiagnosis. A total of 203 females of Lutzomyia longipalpis were subjected to feeding on four cats, with all females completing the blood meal. Parasitological and molecular assays were carried out to evaluate the presence of L. infantum in the sand flies' midgut. Promastigotes were observed in 10 females (6.5%) that fed on one cat, and L. infantum DNA was detected in 17 (8.4%) females that fed on two cats. Our results strengthen the evidence that naturally infected cats are capable of transmitting L. infantum to sand flies. [ABSTRACT FROM AUTHOR]

BACKGROUND: Leishmaniasis is an infectious parasitic disease caused by pathogens of the genus Leishmania transmitted through the bite of adult female sand flies. To reduce case numbers, it is necessary to combine different control approaches, especially those aimed at the sand fly vectors. Innovative forms of control with the use of attractive sugar baits explored the fact that adult sand flies need to feed on sugars of plant origin. Leishmania parasites develop in the gut of sand flies, interacting with the sugars in the diet of adults. Recent studies have shown that sugar baits containing plant‐derived compounds can reduce sand fly survival, the number of parasites per gut, and the percentage of infected sand flies. Several synthetic compounds produced from naphthoquinones and pterocarpans have anti‐parasitic activity on Leishmania amazonensis and/or Leishmania infantum in cell culture. This work aimed to assess the inclusion of these compounds in sugar baits for blocking transmission, targeting the development of the Leishmania parasite inside the sand fly vector. RESULTS: We evaluated the attractant or repellent properties of these compounds, as well as of the reference compound N,N′‐diethyl‐m‐toluamide (DEET), in sugar baits. We also observed changes in feeding preference caused by these compounds, looking for anti‐feeding or stimulation of ingestion. Pterocarpanquinone L4 and pentamidine showed attractant and repellent properties, respectively. CONCLUSION: Based on the effects in feeding preference and intake volume, pterocarpanquinone L6, and the pyrazole‐derived compound P8 were chosen as the most promising compounds for the future development of anti‐Leishmania sugar baits. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]