Anthropic effects on sand fly (Diptera: Psychodidae) abundance and diversity in an Amazonian rural settlement, Brazil

Bayesian spatio-temporal modeling to assess the effect of land-use changes on the incidence of Cutaneous Leishmaniasis in the Brazilian Amazon

Cutaneous Leishmaniasis (CL) is a vector-borne disease caused by a protozoan of the genus Leishmania and is considered one of the most important neglected tropical diseases. The Brazilian Amazon Forest harbors one of the highest diversity of Leishmania parasites and vectors and is one of the main focuses of the disease in the Americas. Previous studies showed that some types of anthropogenic disturbances have affected the abundance and distribution of CL vectors and hosts; however, few studies have thoroughly investigated the influence of different classes of land cover and land-use changes on the disease transmission risk. Here, we quantify the effect of land use and land-cover changes on the incidence of CL in all municipalities within the Brazilian Amazon Forest, from 2001 to 2017. We used a structured spatiotemporal Bayesian model to assess the effect of forest cover, agriculture, livestock, extractivism, and- deforestation on CL incidence, accounting for confounding variables such as population, climate, socioeconomic, and spatiotemporal random effects. We found that the increased risk of CL was associated with deforestation, especially modulated by a positive interaction between forest cover and livestock. Landscapes with ongoing deforestation for extensive cattle ranching are typically found in municipalities within the Amazon Frontier, where a high relative risk for CL was also identified. These findings provide valuable insights into developing effective public health policies and land-use planning to ensure healthier landscapes for people.

Evaluation of the biodiversity and distribution of sand flies and tracking of Leishmania major in them in central Iran

Many areas of Iran are endemic regarding Cutaneous leishmaniasis (CL) as a parasitic disease transmitted by a female sand fly vector's bite. The present study investigated the distribution of sand flies in Harand and Egieh in Isfahan province, Central Iran. Overall, 408 out of 1260 collected sand flies were identified morphologically, among which 353 and 55 were isolated from Harand and Egieh, respectively. Also, 66.4% and 33.6% of the sand flies were female and male, respectively. The most prevalent sand fly species were Phlebotomus papatasi (52%), followed by Ph. caucasicus (40.4%), Sergentomyia sintoni (4.9%), and Ph. kazeruni (0.7%). Among 180 molecularly-analyzed sand flies, 14 (7.77%) were found infected with L. major, with 9 out of 103 (8.73%) Ph. papatasi and 5 out of 75 (6.66%) Ph. caucasicus.

Phlebotomine sand flies in rural Mayan communities of Southern Mexico: The heterogeneity of the ruralscape increases the entomological risk

In the Yucatan Peninsula, tropical preserved forests harbor a high diversity of phlebotomine sand fly species, potential vectors of Leishmania. As a result, a significant risk of contracting localized cutaneous leishmaniasis (LCL) is associated with entry into these forest ecosystems. However, with the current trajectory of land use in the region, communities now live within modified landscapes which could increase their risk of contact with vectors. In this study, we characterized the sand fly fauna and its relationship with the characteristics of peridomestic habitats in two rural communities in Yucatan characterized by contrasting records of leishmaniasis. Five human dwellings in each community were randomly selected and the peridomestic landscape was characterized (i.e., type and percentage of land use). For the collection of sand flies, CDC traps were deployed in both the intra and peridomicile. Differences in alpha and beta diversity between communities and ecotopes were estimated considering three separate groups, all species together, zoophilic species, and anthropophilic species. In total, 1, 241 sand flies represented by eight species were collected from November 2021-March 2022. Both communities registered the presence of sand flies in the intra and peridomicile, and females were more abundant than males. However, the greatest diversity of species was recorded in the peridomicile of the community with the highest composition of land uses. Our study demonstrates that the transformation of the forest around the communities favors the abundance and richness of sand flies in the peridomestic environment. We discuss the limitations and implications of our findings regarding the potential risk of the emergence of peri‑rural cycles of leishmaniasis in the region.

Biting rhythms and infection rates of anthropophilic sand fly species (Diptera: Phlebotominae) in sites with different land use in southern Mexico

Could tropical forest conversion shape sand fly (Diptera: Phlebotominae) biting rhythms and Leishmania infection rates? Using a Shannon trap, we estimated the bite rate and infection prevalence among anthropophilic sand flies at sites with different land use in southern Mexico. We estimated the expected monthly infection rate of the Leishmania parasite along the gradient and generated information on the biting rhythm of sand flies in a poorly characterized cutaneous leishmaniasis endemic region. We used generalized mixed linear and mixed additives models to evaluate differences in the biting rate, nocturnal activity, and inoculation rate of female sand flies, as well as their relationship with the loss of forest cover and environmental disparities recorded throughout the study area. Our results show that the loss of forest cover influences the biting rhythm of sand fly species and the potential number of infectious bites with Leishmania, but the greatest entomological and potential epidemiological risk continues to be associated with sylvatic areas (amplification events). Despite this, we detected that the effect of forest cover (%) on the entomological exposure seems to be also dependent on the sand fly species, and that, albeit to a lesser extent, Leishmania parasite is circulating in disturbed landscapes through generalist and competent sand fly vector species. We also found that land use change did not affect the nocturnal activity, however we detected that important vector species were active most of the time. Contrary to our expectation, temperature and humidity did not shape the biting rhythm of sand fly species. We discuss the limitations and epidemiological implications of our findings regarding the risk of contracting leishmaniasis in southern Mexico.

Ecology and natural infection of phlebotomine sand flies in different ecotopes and environments in the municipality of Pains, Minas Gerais, Brazil

Phlebotomines (Diptera: Psychodidae) are vectors of protozoa of the genus Leishmania and distributed throughout Brazil, formerly restricted to rural areas, have expanded including to periurban and urban regions, been recorded in different habitats. This study aimed to understand the dynamics of sand flies in different ecotopes in the municipality of Pains. Sand flies were captured during thirty samplings using HP light traps installed in seven different ecotopes for two consecutive nights, once a month, from August 2018 to July 2019. A total of 1,352 sand flies were captured, representing 24 species belong to ten genera. Evandromyia edwardsi was the most abundant species, followed by Evandromyia lenti and Micropygomyia quinquefer. Leishmania DNA was detected in seven female sand flies in four ecotopes, for an infection rate of 0.9%. Sand flies were collected in all seven ecotopes, although forest (23.04%), cave (20.88%) and pasture (17.75%) had higher abundance and richness. Similarity was found among ecotopes, indicating that they are all important for the maintenance of the sand fly community. Spatial analysis indicated high densities of sand flies in areas with natural characteristics. All ecotopes in the municipality were evidenced to have an adequate and harmonious epidemiological profile for the transmission and expansion of leishmaniasis throughout the territory. Because of the increasing environmental changes and deforestation in the municipality, the risk of generating ecological imbalance and increased cases of leishmaniasis is imminent, which highlights the importance of developing preventive and control strategies.

Ecological Aspects of the Phlebotominae Fauna (Diptera: Psychodidae) among Forest Fragments and Built Areas in an Endemic Area of American Visceral Leishmaniasis in João Pessoa, Paraíba, Brazil

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.

Diversity of cave Phlebotomines (Diptera: Psychodidae) from a Colombian cave

Sandflies are vector species of Leishmania, among many other pathogens, with a global distribution and a variety of ecological niches. Previous samplings have found that karstic formations (i.e., caves, grottos, and folds formed by the erosion of limestone) serve as a natural habitat to sandfly species. The majority of samplings of cave sandfly diversity have occurred in Brazil and to date none have studied the species composition in a cave in the Northern Andes. We collected sandflies in the Cave "Los Guácharos", in the state of Antioquia, Colombia. The sampling was carried out during two consecutive nights in September 2019. CDC-type light traps were installed inside the cavern and in other surrounding karst systems (caves, rock-breaks, and folds). In total, we identified 17 species of sandfly from the cave and surrounding karst systems, including a new record for Colombia (Bichromomyia olmeca), and provide the first karstic reports for four other species (Lutzomyia gomezi, Lutzomyia hartmanni, Pintomyia ovallesi, and Psychodopygus panamensis). We then used the results of our survey and published literature to test two hypotheses. First, that sandfly diversity in Neotropical caves is richest nearer to the equator, and second that there is a phylogenetic signal of karstic habitat use in sandflies. Counter to our predictions, we found no evidence that diversity follows a latitudinal gradient. Further, we find no evidence of a phylogenetic signal of karstic habitat use, instead finding that the use of caves likely evolved multiple times across several genera. Our results highlight the importance of a wide sampling to understand the natural habitat of sandflies and other disease vectors.

Effect of land use change on the phlebotomine sand fly assemblages in an emergent focus of cutaneous leishmaniasis in Yucatan, Mexico

As land use intensifies in tropical forests, it is expected that species assemblages will be modified and that key functions of these ecosystems will be affected. The latter scenario is important from a public health perspective, because the land use change has been linked the outbreaks of vector-borne diseases. In this study, we evaluated the response of Phlebotominae (Diptera: Psychodidae) assemblages and their pattern of co-occurrence in four sites with different land use in an emerging cutaneous leishmaniasis focus in Yucatan, Mexico. Our hypothesis is that the conservation status (as forest cover) will positively influence the structure and composition of sand flies' assemblages. Using three different traps over a period of five months, a sampling effort of 1, 440 night-traps was performed. A total of 7, 897 sand fly specimens belonging to six genera and 10 species were collected. Our hypothesis was partially achieved since sand fly diversity increased as forest cover increased and vice versa, however random patterns of co-occurrence in assemblages were detected among sites. Even though the high abundance of sand flies in the forest fragment suggests an amplification effect, our results show that different vector species directly dominate in each site. We discuss the potential implications of the nestedness of species dominance. We suggest that in this emerging focus and under the land use gradient, Lutzomyia cruciata and Psathyromyia cratifer could play a pivotal role in maintaining the transmission cycles of Leishmania. The apparent generalist or colonialist profile of Lu. cruciata in disturbed areas deserves attention, due to the potential risk of leishmaniasis "domiciliation". This information is essential to understand the eco-epidemiology of leishmaniasis and the factors associated with its emergence in Yucatan, Mexico.

Sand fly bioecological aspects and risk mapping of leishmaniasis by geographical information systems approach in a mineral exploration area of Brazil

Epidemiological studies of leishmaniasis in areas of great human influence and environmental change serve as important tools for the implementation of effective control plans. Mining is currently a major economic activity in Brazil with the municipality of Pains, in the state of Minas Gerais, being one of the main lime producing municipalities in the country. This study aimed to map areas of potential transmission risks within the municipality of Pains using an epidemiological approach in association with the ecological study of sand flies. Twelve samplings carried out between May 2015 and April 2016 collected a total of 12,728 sandflies, comprising 2,854 females (22.42%) and 9,874 males (77.58%), of 20 species belonging to ten genera. The most abundant species was Lutzomyia longipalpis (80%). Leishmania DNA was detected in seven pools of female sand flies with an infection rate of 0.37%. Geoprocessing and the use of maps revealed that vector sand flies are distributed throughout the urban area, as are cases of canine and human leishmaniasis. However, the greatest abundances of sand flies were at sampling points at the border of the urban area. Higher densities of sand flies and the presence of Leishmania DNA may be correlated with extensive degradation by limestone mining. Integrated and multidisciplinary research approaches are necessary to better understand how the impacts of environmental change influence these insect vectors of leishmaniasis.

Factors associated with the expansion of leishmaniasis in urban areas: a systematic and bibliometric review (1959-2021)

This work describes a systematic and bibliometric review of the factors that contribute to the expansion of leishmaniasis in urban areas. Three scientific databases were used: Scientific Electronic Library (SciELO), Scopus and Web of Science, encompassing all original and review articles between 1959 and 2021. Three descriptors were used: "leishmaniasis" AND "urban" AND "rural." Planning, execution, summarization, and selection processes were performed using StArt (State of the Art through Systematic Review) software. We obtained a total of 304 articles, 60 of which concerned canine leishmaniasis. The factors associated with the expansion of leishmaniasis in urban areas are interrelated, including socioenvironmental and economic complexity, the type of leishmaniasis, the reservoirs, vectors, deforestation, disorderly occupation of space, poor sanitary conditions, and human migration trends. A lack of diagnosis and underreporting of cases in some regions may reflect the increase of cases seen in urban areas. A majority (n = 121) of studies were conducted in Brazil, followed by Iran (n = 43). In relation to publications; in general, output has increased over the years, particularly in 2021. The majority of published studies were in the area of epidemiology (n = 158).

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

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

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

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

Redescription of Two Psathyromyia Species (Diptera: Psychodidae), Including Description of the Female of Psathyromyia pradobarrientosi Using Molecular and Morphological Approaches

The taxonomic identity of two species of sand flies, Psathyromyia pradobarrientosi (Le Pont, Matias, Martinez & Dujardin, 2004) and Psathyromyia runoides (Fairchild & Hertig, 1953) (Diptera, Psychodidae), was evaluated morphologically and molecularly based upon specimens collected in Brazilian states. The morphological component compared collected specimens with paratypes of Pa. runoides and Pa. pradobarrientosi and their descriptions. Phylogenetic analysis of coI sequences of Pa. pradobarrientosi showed a well-supported group distinct from Pa. runoides. Morphologically, Psathyromyia runoides and Pa. pradobarrientosi males are distinguished by characteristics of the aedeagal ducts and parameral sheath in the genitalia; females are distinguished by the number and shape of the teeth in the cibarium and by the shape of the spermathecae. Given the morphological similarity between the males and the absence of the description of the female of Pa. pradobarrientosi, it is possible that specimens previously identified as Pa. runoides in Brazil are in fact Pa. pradobarrientosi.

Distribution and diversity of mosquitoes and Oropouche-like virus infection rates in an Amazonian rural settlement

Mosquito diversity and disease transmission are influenced by landscape modifications, i.e., vectors and pathogens previously found only in forests are now found close to human environments due to anthropic changes. This study determined the diversity and distribution of mosquitoes in forest environments in order to analyze the potential vectors of Amazonian forest arboviruses. Mosquitoes were collected by 1) vertical stratification from forest canopy and ground areas using Hooper Pugedo (HP) light traps and human attraction and 2) horizontal stratification using HP light traps in peridomicile, forest edge, and forest environments near the Rio Pardo rural settlement, Amazonas, Brazil. A total of 3,750 mosquitoes were collected, representing 46 species. 3,139 individuals representing 46 species were sampled by vertical stratification. Both the Shannon-Weaver diversity index (H’) and equitability (J’) were higher in the canopy than on the ground. 611 individuals representing 13 species were sampled by horizontal stratification. H’ decreased in the following order: forest edge > forest > peridomicile, and J’ was greater at the forest edge and smaller in the peridomicile environment. Moreover, H’ was higher for the human attraction collection method than the HP traps. A total of 671 pools were analyzed by RT-qPCR; three species were positive for Oropouche-like viruses (Ochlerotatus serratus, Psorophora cingulata, and Haemagogus tropicalis) and the minimum infection rate was 0.8%. The composition of mosquito species did not differ significantly between anthropic and forest environments in Rio Pardo. Some mosquito species, due to their abundance, dispersion in the three environments, and record of natural infection, were hypothesized to participate in the arbovirus transmission cycle in this Amazonian rural settlement.

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

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

Level of Knowledge and Risk Factors for Visceral Leishmaniasis in a Mining Area of Minas Gerais State, Brazil

Aiming to optimize and adjust leishmaniasis prevention and control measures for the resident population of Pains, state of Minas Gerais, Brazil, a structured questionnaire containing conceptual questions and questions about household characteristics was used to evaluate knowledge level and exposure risk. A total of 396 individuals were interviewed revealing unscientific and fragmented knowledge about the subject for most of the studied population. The female population was found to have 1.68 times more chance of knowing about the disease than the male population, while highly educated individuals were found to have 2.92 times more chances of knowing about leishmaniasis compared to basic educated individuals. All of the respondents reported the presence of, at least, one risk factor, while ages ≥40 years were considered a protective factor compared to younger ages, indicating that older individuals are more likely to recognize risks and protect themselves against leishmaniasis. These results will contribute to the production of didactic materials for the population with respect to their previous knowledge and will provide a basis for control and prophylactic measures.

Variation of the Phlebotominae (Diptera: Psychodidae: Phlebotominae) Assemblage in Response to Land Use Changes in an Endemic Area of Leishmania Transmission in Northeast Argentina

Leishmaniases are a global health problem and in Argentina are considered emerging diseases. The new transmission scenarios of tegumentary leishmaniasis are especially important given that large areas of forest are being transformed into rural and urban systems. The aim of this study was to analyze the impact of the construction of a large public building and a neighborhood on the assemblage of Phlebotominae in a rural area with forest remnants and to correlate the changes observed in the species assemblage with characteristics of the environment. Entomological surveys with light traps were conducted on the construction campus in the northeastern region of Argentina at six sites representing different environmental situations. Structural environmental characteristics and meteorological conditions were recorded and analyzed. At least 16 species of Phlebotominae sand flies were collected, the most prevalent being Nyssomyia whitmani (Antunes & Coutinho), followed by the genus Brumptomyia (França & Parrot) and Migonemyia migonei (França). Our study provides evidence of how the structure of the assemblages and prevalent species respond to anthropogenic disturbances. As the construction progressed, both Ny. whitmani and the genus Brumptomyia were favored. The genus Brumptomyia was favored at sites surrounded by high proportions of forest, within patches of remnant vegetation, and relatively far from anthropogenic disturbances, while Ny. whitmani, the main vector of tegumentary leishmaniasis in the region, increases their abundant at short and intermediate distances from vegetation margins and areas close to anthropogenic disturbances, therefore increasing the risk of human exposure to vectors.

Landscape effects on the abundance of Lutzomyia longipalpis and Migonemyia migonei (Diptera: Psychodidae: Phlebotominae) in Corrientes city, northern Argentina

We analyses the relationship between landscape and environmental variables estimated from high-resolution satellite images with the temporal variation of the abundance of Lutzomyia longipalpis and Migonemyia migonei, vectors of leishmaniasis, in Corrientes city. At 8 collection sites, 14 samples were conducted between March 2012 to February 2014. Proportion of land cover classes derived from high resolution satellite images as: water, bare soil, urban areas, low vegetation and high vegetation, as well as average, maximum and minimum values of Normalized Difference Vegetation Index and Normalized Difference Water Index) in buffer areas of 50 m, 100 m and 150 m were used to characterize and identify suitable environmental conditions for the development of sand flies through Generalized Linear Mixed Models. The most frequently collected species during the sampling period was Lu. longipalpis and followed by Mg. migonei. The models showed that high Lu. longipalpis abundance were related to low proportion of high vegetation coverage, while a negative association was among Mg. migonei abundance and with values of Normalized Difference Water Index and with the interaction between urban areas and minimum values of Normalized Difference Water Index, and a positive association with the interaction between low vegetation and average values of Normalized Difference Water Index.

The Effect of Anthropization on Sarcophagidae (Diptera: Calyptratae) Community Structure: An Assessment on Different Types of Habitats in the Humid Chaco Ecoregion of Argentina

Sarcophagidae (Diptera) are of great interest from a veterinary, medical, and forensic viewpoint, and are potential bioindicators for environmental impact assessments. In this study, we evaluated changes in abundance, species richness, and diversity of flesh flies in different habitat types in the Humid Chaco ecoregion of South America: 1) anthropized habitats: urban, cattle farm, and alfalfa crop, and 2) natural habitats: savanna and forest. We hypothesized that sarcophagid fly community parameters are affected by the anthropization and that spatial turnover will contribute more to the overall beta diversity than nestedness between habitats. In each habitat, samplings were conducted monthly from March 2015 to February 2016 in 25 sites, 5 per habitat, totaling 300 independent samples at the end of the study. We collected 5,790 Sarcophagidae (55 species). Community parameters of Sarcophagidae were evaluated and compared. The ecological effects of anthropization and habitat type were observed in the present study. As expected, our results showed the highest abundance, species richness, and diversity in the savanna and forest habitats (natural), whereas the lowest values were registered in the urban and alfalfa crop habitats, supporting the hypotheses of anthropization as the main driver of diversity loss. In addition, sarcophagid assemblages differed between all habitats and the overall dissimilarity was structured by spatial turnover. The main conclusion of this research is that flesh fly community structure is greatly affected by anthropization and habitat type, and this would be related to canopy cover and microclimate conditions of each environment.

Under the light: high prevalence of haemoparasites in lizards (Reptilia: Squamata) from Central Amazonia revealed by microscopy

Blood samples from 330 lizards of 19 species were collected to investigate the occurrence of haemoparasites. Samplings were performed in areas of upland (terra-firme) forest adjacent to Manaus municipality, Amazonas, Brazil. Blood parasites were detected in 220 (66%) lizards of 12 species and comprised four major groups: Apicomplexa (including haemogregarines, piroplasms, and haemosporidians), trypanosomatids, microfilarid nematodes and viral or bacterial organisms. Order Haemosporida had the highest prevalence, with 118 (35%) animals from 11 species. For lizard species, Uranoscodon superciliosus was the most parasitised host, with 103 (87%; n = 118) positive individuals. This species also presented the highest parasite diversity, with the occurrence of six taxa. Despite the difficulties attributed by many authors regarding the use of morphological characters for taxonomic resolution of haemoparasites, our low-cost approach using light microscopy recorded a high prevalence and diversity of blood parasite taxa in a relatively small number of host species. This report is the first survey of haemoparasites in lizards in the study region. It revealed a high diversity of lizard haemoparasites and highlights the need to understand their impacts on hosts.

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

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

A systematic review of biodiversity and demographic change: A misinterpreted relationship?

Demographic change is supposed to be the most important indirect driver for changing biodiversity. In this article, a systematic review of 148 studies was conducted to examine the scientific evidence for this relationship and to identify potential gaps in research. We explored the spatial distribution of studies, the categories addressed with respect to biodiversity and demographic change, and the ways in which their relationships were conceptualised (spatially and temporally) and valued. The majority of studies were carried out in Africa, Europe and North America. Our analysis confirms the trend that demographic phenomena were mostly found to negatively influence biodiversity. However, a considerable number of studies also point towards impacts that were context dependent, either positive or negative under certain circumstances. In addition to that we identified significant gaps in research. In particular, there is a lack of addressing (1) other demographic aspects such as population decline, age structure or gender differences, (2) spatial variability of, e.g. human population growth, (3) long-term effects of demographic processes, and (4) the context dependency (e.g. regulations/law enforcement, type of human activities, and choice of scale or proxy). We conclude there is evidence that the relationship between biodiversity and demographic change is much more complex than expected and so far represented in research. Thus, we call for a social-ecological biodiversity research that particularly focusses on the functional relation between biodiversity and human activities, namely the different types, context, and interdependent dynamics (spatial and temporal) of this complex relation.

Diversity of biting midges Culicoides (Diptera: Ceratopogonidae), potential vectors of disease, in different environments in an Amazonian rural settlement, Brazil

INTRODUCTION:

The Culicoides transmit a variety of pathogens. Our aim was to survey the Culicoides species occurring in an Amazonian rural settlement, comparing abundance, richness, and diversity in different environments.

METHODS:

Culicoides were captured using CDC light traps. The Shannon-Wiener (H’) and Rényi indices were used to compare species diversity and evenness between environments, the equitability (J’) index was used to calculate the uniformity of distribution among species, and similarity was estimated using the Jaccard similarity index. A permutational multivariate analysis of variance was applied to assess the influence of environment on species composition. A non-metric dimensional scale was used to represent the diversity profiles of each environment in a multidimensional space.

RESULTS:

6.078 Culicoides were captured, representing 84 species (45 valid species/39 morphotypes). H’ values showed the following gradient: forest > capoeira > peridomicile > forest edge. The equitability J’ was greater in capoeira and forests compared to peridomiciles and the forest edge. The population compositions of each environment differed statistically, but rarefaction estimates indicate that environments of the same type possessed similar levels of richness. Species of medical and veterinary importance were found primarily in peridomiciles: C. paraensis, vector of Oropouche virus; C. insignis and C. pusillus, vectors of Bluetongue virus; C. filariferus, C. flavivenula, C. foxi, and C. ignacioi, found carrying Leishmania DNA.

CONCLUSIONS:

This study indicates that diversity was higher in natural environments than in anthropized environments, while abundance and richness were highest in the most anthropized environment. These findings suggest that strictly wild Culicoides can adapt to anthropized environments.

Ecological niche modelling for predicting the risk of cutaneous leishmaniasis in the Neotropical moist forest biome

A major challenge of eco-epidemiology is to determine which factors promote the transmission of infectious diseases and to establish risk maps that can be used by public health authorities. The geographic predictions resulting from ecological niche modelling have been widely used for modelling the future dispersion of vectors based on the occurrence records and the potential prevalence of the disease. The establishment of risk maps for disease systems with complex cycles such as cutaneous leishmaniasis (CL) can be very challenging due to the many inference networks between large sets of host and vector species, with considerable heterogeneity in disease patterns in space and time. One novelty in the present study is the use of human CL cases to predict the risk of leishmaniasis occurrence in response to anthropogenic, climatic and environmental factors at two different scales, in the Neotropical moist forest biome (Amazonian basin and surrounding forest ecosystems) and in the surrounding region of French Guiana. With a consistent data set never used before and a conceptual and methodological framework for interpreting data cases, we obtained risk maps with high statistical support. The predominantly identified human CL risk areas are those where the human impact on the environment is significant, associated with less contributory climatic and ecological factors. For both models this study highlights the importance of considering the anthropogenic drivers for disease risk assessment in human, although CL is mainly linked to the sylvatic and peri-urban cycle in Meso and South America.

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

BACKGROUND

The state of Rondônia (RO) is a hot spot for human cases of cutaneous leishmaniasis. Many sandfly species in RO are putative vectors of leishmaniasis.

OBJECTIVES

This study examines the diversity patterns and the presence of Leishmania DNA and blood meal sources of sandflies in RO.

METHODS

A sandfly survey was performed between 2016 and 2018 in 10 municipalities categorised into three different environment types: (i) Conservation Unit (CUN) - comprised of preserved ombrophilous forests; (ii) Forest Edge (FE) - small forest fragments; and (iii) Peridomicile (PE) - areas around dwellings.

FINDINGS

A total of 73 species were identified from 9,535 sandflies. The most abundant species were Psychodopygus davisi (1,741 individuals), Nyssomyia antunesi (1,397), Trichophoromyia auraensis (1,295) and Trichophoromyia ubiquitalis (1,043). Diversity was the highest in CUN, followed by the FE and PE environments. One pool of Ps. davisi tested positive for Leishmania braziliensis, reinforcing the possibility that Ps. davisi acts as a vector. The cytochrome b (cytb) sequences were used to identify three blood meal sources: Bos taurus, Homo sapiens and Tamandua tetradactyla.

MAIN CONCLUSIONS

Our results demonstrated that sandflies can switch between blood meal sources in differing environments. This study enhances the knowledge of the vector life cycle in RO and provides information relevant to leishmaniasis surveillance.

Leishmania DNA detection and species characterization within phlebotomines (Diptera: Psychodidae) from a peridomicile-forest gradient in an Amazonian/Guianan bordering area

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.

Influence of Deforestation on the Community Structure of Sand Flies (Diptera: Psychodidae) in Eastern Amazonia

Variation in the structure of phlebotomine (sand fly) communities in forest fragments with different degrees of preservation and human occupation (peridomicile) in eastern Amazonia was studied. We identified 43 species of sand flies in our study, of which 38 occurred in both preserved forest areas and in the peridomiciles of short-term settlements, while another 28 species occurred in altered forest fragments and long-term settlements. The composition of the community at each site changed with the type of environment (forest or peridomicile), with the species Lutzomyia evandroi, L. whitmani, L. choti, L. serrana, L. triacantha, L. migonei, L. hirsuta, L. shannoni, and L. brachyphylla accounting for more than 54% of the differences among environments. The quality of the environment exerted a significant influence on the structure of phlebotomine communities, and affected their species composition, richness, and abundance.

Sand Fly Fauna Associated With Dwellings and Forest Habitats Along the BR-319 Highway, Amazonas, Brazil

Roads and highways can affect the spread of insect-borne diseases by limiting or amplifying the spatiotemporal distribution of vectors, pathogens, and hosts, which can, in turn, lead to the creation of a nidus of infection. The aim of this study was to compare the diversity (richness and abundance) of phlebotomine sand flies in household and forest edge environments found along two different segments of an Amazonian highway. Sampling was conducted along the northern and southern portions of highway BR-319, in Amazonas State, Brazil. At each sampling point, Hoover Pugedo traps were set in indoor and outdoor habitats, and at forests edges, and captures were made between 06:00 pm and 06:00 am. A total of 1,189 sand flies were captured and 48 species were identified. As expected, a greater number of species and individuals were captured in forest edge environments. Permutational Multivariate Analyses of Variance (PERMANOVA) and Permutational Analyses of Multivariate Dispersions (PERMDISP) analyses showed that sand fly fauna differed significantly among habitats, but no variance in species composition was observed between the two road segments. Some of the captured species were species that have been implicated as vectors of Leishmania spp. Ross, 1903 (Kinetoplastida: Trypanosomatidae).

The role of deforestation on American cutaneous leishmaniasis incidence: spatial-temporal distribution, environmental and socioeconomic factors associated in the Brazilian Amazon

OBJECTIVE

To analyse the temporal and spatial distribution as well as the environmental and socioeconomic factors associated with cutaneous leishmaniasis incidence in the state of Amazonas, Brazil from 2007 to 2015.

METHODS

Spatial and temporal distribution was evaluated from sequential thematic maps of the mean incidence rates of the disease. A negative binomial regression analysis was performed to evaluate the association of the factors studied with the mean incidence rate of ACL.

RESULTS

The average proportion of deforestation was negatively associated with the average incidence rate of cutaneous leishmaniasis in municipalities (β = -2.178; P = 0.019; 95%CI -3.996, -0.361), and the health system performance index (effectiveness) (β = -0.852; P = 0.008; 95%CI -1.481, -0.225). Conversely, the municipal human development index (MHDI) was a factor positively related to the average incidence among the municipalities (β = 7.728; P = 0.003; 95%CI 2.716, 12.738).

CONCLUSION

Our study shows the important impact of socioeconomic and environmental factors on ACL incidence in the Amazonas State.

Ecological aspects of Phlebotomines (Diptera: Psychodidae) and the transmission of American cutaneous leishmaniasis agents in an Amazonian/ Guianan bordering area

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.

Vegetation Cover and Microspatial Distribution of Sand Flies (Diptera: Psychodidae) in an Endemic Locality for Cutaneous Leishmaniasis in Northern Argentina

The sand fly fauna in Hipólito Yrigoyen, Argentina, a locality where cutaneous leishmaniasis cases occur, was surveyed with zones of higher abundance of sand flies correlated to vegetation cover estimated through normalized difference vegetation index (NDVI). Sand flies were collected with 10 CDC traps during six nights, from December 2009 to January 2010. A map was built of expected sand flies abundance in which levels of NDVI were categorized. In total, 1,392 Phlebotominae (Diptera: Psychodidae) specimens were collected, comprised of the following species: Nyssomyia neivai (Pinto 1926), Migonemyia migonei (França 1920), species of the cortelezzii complex (Brèthes 1923), Evandromyia sallesi (Galvão & Coutinho 1940), and Psathyromyia shannoni (Dyar 1929). Positive correlations were found between the abundance of sand flies and the NDVI (P < 0.05) for buffer areas of <150 m radii from the trap location points, i.e., the sand fly abundance was greater where vegetation cover and density were greater. In this context, plant cover should be taken into account to prioritize surveillance and control areas within the program of sand flies control in northern Argentina.

Critical linkages between land use change and human health in the Amazon region: A scoping review

Land use change (LUC) is a main cause of global environmental change, and is an important activity to be studied. Our research aims to examine the current state of evidence on the link between LUC and human health in the Amazon region. We conducted a scoping review of literature in two research databases, resulting in 14 papers for analysis. Our analysis demonstrated a lack of clear definitions for LUC, a wide variety of negative health effects from LUC, the lack of qualitative articles, a lack of studies exploring the potential positive health effects of LUC, and the predominance of studies coming from the Brazilian Amazon. Our study validated the prevailing idea that LUC can lead to negative health consequences, if not managed properly.

Entomological surveys of Lutzomyia flaviscutellata and other vectors of cutaneous leishmaniasis in municipalities with records of Leishmania amazonensis within the Bragança region of Pará State, Brazil

In southeast Amazon, Lutzomyia (Nyssomyia) flaviscutellata is the incriminated vector of Leishmania (Leishmania) amazonensis, a causative agent of zoonotic cutaneous leishmaniasis (CL). The optimal methods for surveying Lu. flaviscutellata were investigated in the Bragança region, northeast Pará State, Brazil, selected for the presence of Le. amazonensis. The performances of modified Disney traps and CDC light traps were compared in four ecotopes within and around four village transects during the wet and dry seasons. The physiological age of female sand flies was estimated and natural infection by flagellates was evaluated by dissection. Disney traps were better for detecting the presence of Lu. flaviscutellata, while CDC traps performed well for detecting Lutzomyia (Nyssomyia) antunesi, suspected vector of Leishmania lindenbergi. The former was more abundant during the wet season, when female flies were naturally infected with Le. amazonensis. These findings identified the environments of local transmission. In order to improve surveys of Lu. flaviscutellata as part of integrated epidemiological surveillance of CL, our recommendations include focusing vector surveys with Disney traps on forest fragments where people work, during the seasonal peak of the vector. Further field studies are required to make model-based predictions of seasonal variations in the vectorial capacity of vector populations.

Composition of sand fly fauna (Diptera: Psychodidae) and detection of Leishmania DNA (Kinetoplastida: Trypanosomatidae) in different ecotopes from a rural settlement in the central Amazon, Brazil

Background

Phlebotomine sand flies (Diptera: Psychodidae) are vectors of Leishmania species, the etiological agents of leishmaniasis, which is one of the most important emerging infectious diseases in the Americas. In the state of Amazonas in Brazil, anthropogenic activities encourage the presence of these insects around rural homes. The present study aimed to describe the composition and distribution of sand fly species diversity among the ecotopes (intradomicile, peridomicile and forest) in an area of American cutaneous leishmaniasis transmission and detect natural infection with Leishmania DNA to evaluate which vectors are inside houses and whether the presence of possible vectors represents a hazard of transmission.

Results

Phlebotomine sand flies were collected using light traps. A total of 2469 specimens representing 54 species, predominantly females (71.2%), were collected from four sites. Polymerase chain reaction analysis was performed on 670 samples to detect Leishmania DNA. Most of the samples (79.5%) were collected in the forest, with areas closer to rural dwellings yielding a greater abundance of suspected or proven vectors and a larger number of species containing Leishmania DNA. Nyssomyia umbratilis and Bichromomyia flaviscutellata were found near rural homes, and Ny. umbratilis was also found inside homes. Leishmania DNA was detected in different species of sand flies in all ecotopes, including species with no previous record of natural infection.

Conclusions

There is no evidence that vectors of American cutaneous leishmaniasis are becoming established inside homes, but there are sand flies, including Ny. umbratilis and other possible vectors, in environments characterized by a human presence. These species continue to be predominant in the forest but are prevalent in areas closer to ecotopes with a greater human presence. The existence of proven or suspected vectors in this ecotope is due to the structural organization of rural settlements and may represent a hazard of transmission. Although the detection of Leishmania DNA in species that were not previously considered vectors does not mean that they are transmitting the parasite, it does show that the parasite is circulating in ecotopes where these species are found.

New Records of Phlebotomine Sand Flies (Diptera: Psychodidae) From the State of Alagoas, Northeast of Brazil

Phlebotomine sand flies are small insects of great medical importance. This study presents new records of phlebotomine sand flies, which augment the list of species, recorded in the state of Alagoas, Brazil. Sand flies were collected using CDC miniature light traps. Collections were made between November 2008 and April 2016, in 47 municipalities within the state of Alagoas. Twenty-seven thousand two-hundred forty-four sand flies were collected, representing 18 species in seven genera. Lutzomyia longipalpis was the predominant species (85.4% of total), and it was recorded in all biomes. Three species (Evandromyia evandroi (Costa Lima and Antunes 1936), Evandromyia tupynambai (Mangabeira 1942), and Pressatia choti (Floch and Abonnenc 1941)) were collected in coastal and Atlantic forest biomes; five species (Lutzomyia villelai (Mangabeira 1942), Micropygomyia oswaldoi (Mangabeira 1942), Nyssomyia umbratilis (Ward and Frahia 1977), Nyssomyia intermedia (Lutz and Neiva 1912), and Nyssomyia whitmani (Antunes and Coutinho 1939)) were collected in Atlantic forest and Caatinga biomes. The species Evandromyia corumbaensis (Galati, Nunes, Oshiro and Rego 1989) and Psathyromyia naftalekatzi (Falcão, Andrade-Filho, Almeida and Brandão-Filho 2000) were found only in the coastal zones. This work provides an updated list of the phlebotomine sand flies of Alagoas, with some notes on their taxonomy, ecology, distribution, and epidemiological relevance.

Phlebotomine sandfly (Diptera: Psychodidae) diversity and their Leishmania DNA in a hot spot of American Cutaneous Leishmaniasis human cases along the Brazilian border with Peru and Bolivia

In this study, we identified the phlebotomine sandfly vectors involved in the transmission of American Cutaneous Leishmaniasis (ACL) in Assis Brasil, Acre, Brazil, which is located on the Brazil-Peru-Bolivia frontier. The genotyping of Leishmania in phlebotomines was performed using polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism. A total of 6,850 sandflies comprising 67 species were captured by using CDC light traps in rural areas of the municipality. Three sandfly species were found in the state of Acre for the first time: Lutzomyia georgii, Lu. complexa and Lu. evangelistai. The predominant species was Lu. auraensis/Lu. ruifreitasi and Lu. davisi (total 59.27%). 32 of 368 pools were positive for the presence of Leishmania DNA (16 pools corresponding to Lu. davisi, and 16 corresponding to Lu. auraensis/Lu. ruifreitasi), with a minimal infection prevalence of 1.85% in Lu. davisi and 2.05% in Lu. auraensis/Lu. ruifreitasi. The Leishmania species found showed maximum identity with L. (Viannia) guyanensis and L. (V.) braziliensis in both phlebotomine species. Based on these results and similar scenarios previously described along the Brazil/Peru/Bolivia tri-border, the studied area must take into consideration the possibility of Lu. davisi and Lu. auraensis/Lu. ruifreitasi as probable vectors of ACL in this municipality.

Phlebotomine Sand Fly Composition (Diptera: Psychodidae) and Putative Vectors of American Cutaneous Leishmaniasis in Porto Velho Municipality, Western Amazon, Brazil

This study evaluated the species composition of sand flies and identified potential vectors of Leishmania Ross species in rural areas of Porto Velho, Rondônia State, Brazil. American cutaneous leishmaniasis (ACL) is one of the gravest threats to public health in this state. Sand flies were collected over the course of 2014 and 2015 using HP light traps. Polymerase chain reaction was performed by targeting the Leishmania mkDNA region. In total, 2,344 sand flies were collected, from which 45 species, nine subgenera, and five species group were identified. The most abundant species were Lutzomyia antunesi (Coutinho) (n = 597, 25.47%), Lutzomyia ubiquitalis (Mangabeira) (n = 496, 21.16%), and Lutzomyia octavioi (Vargas) (n = 199, 8.49%). The greatest diversity occurred in the forest environment where the most abundant species were L. antunesi (n = 588, 25.07%), L. ubiquitalis (n = 493, 21.02%), L. octavioi (n = 199, 8.49%), and Lutzomyia flaviscutellata (Mangabeira) (n = 132, 5.63%). Two pools of L. ubiquitalis were positive for Leishmania DNA, which suggests that L. ubiquitalis is a putative vector of leishmaniasis in the municipality of Porto Velho.

Revalidation of Nyssomyia fraihai (Martins, Falcão & Silva 1979) (Diptera: Psychodidae)

Lutzomyia fraihai (Martins, Falcão & Silva 1979), described from Três Braços municipality (Bahia state, Brazil), is closely related to Nyssomyia yuilli yuilli (Young & Porter, 1972), described from Rio Anori, Antioquia, Colombia. The former species, despite the morphological differences reported by its authors, was included as a junior synonym of Ny. yuilli yuilli, and this status has been accepted by sand fly-taxonomists. However, we had an opportunity to examine both taxa, and a clear difference was noted in their male genitalia. In this study, the morphometric/morphologic characters of specimens that had been identified as Ny. yuilli yuilli from different localities (Brazil, Peru, Colombia, Bolivia) and type material of both Ny. yuilli yuilli and Lu. fraihai were analyzed. The results revealed that males from Brazil (Bahia, Acre, Pará, and Rondônia states) and Peru present statistically significant differences in the ratio between paramere rectangular and digitiform areas as well as for the cercus length and width of the aedeagal ducts tips, when compared with the type specimens of Ny. yuilli yuilli, but are statistically similar to those characters of Lu. fraihai However, females of the two species are indistinguishable. Thus, based on the male morphology, Ny. fraihai STAT REV N COM: was resurrected from the synonymy of Ny. yuilli yuilli. The specimens from the Atlantic forest biome and the Amazon biome in Brazil, Peru, and Bolivia in fact belong to Ny. fraihai This species presents a cis-Andean distribution, while Ny. yuilli yuilli has been found in both Andean and Trans-Andean areas.

Seasonal biodiversity of black flies (Diptera: Simuliidae) and evaluation of ecological factors influencing species distribution at Doi Pha Hom Pok National Park, Thailand

This is the first study on the seasonal biodiversity of black flies and evaluation of ecological factors influencing their distribution at Doi Pha Hom Pok National Park, northern Thailand. Larvae were collected from six fixed-stream sites in relation to altitude gradients from May 2011 to April 2013. The water temperature, water pH, conductivity, total dissolved solids (TDS), salt, water velocity, stream width and depth, streambed particle sizes, riparian vegetation, and canopy cover were recorded from each site. Monthly collections from the six sites yielded 5475 last-instar larvae, belonging to 29 black fly species. The most frequently found species from all sites were Simulium asakoae (100%) followed by Simulium yuphae (83.3%), and Simulium chiangdaoense, Simulium gombakense, Simulium phahompokense, Simulium fruticosum, Simulium maeaiense and Simulium fenestratum (66.6%). Of the 5475 last-instar larvae, S. maeaiense (19.3%), S. chiangdaoense (15.8%) and S. asakoae (14.8%), were the three most abundant species. The Shannon diversity index (H) at the six sites with different altitudes of 2100m, 2000m, 1500m, 1400m, 700m, and 500m above mean sea level, were 2.042, 1.832, 2.158, 2.123, 1.821 and 1.822, respectively. The Shannon index and number of taxa in the cold season were higher than those in the rainy and hot seasons. Principal component analysis (PCA) indicated that at least three principal components have eigen values >1.0 and accounted for 93.5% of the total variability of ecological factors among sampling sites. The Canonical correspondence analyses (CCA) showed that most species had a trend towards altitude, canopy cover, riparian vegetation and water velocity.

An ecological study of sand flies (Diptera: Psychodidae) in the vicinity of Lençóis Maranhenses National Park, Maranhão, Brazil

Background

The Lençóis Maranhenses National Park, located in Maranhão, Brazil, is a region of exceptional beauty and a popular tourist destination. The adjoining area has suffered from the impact of human activity and, consequently, has experienced outbreaks of leishmaniasis. This study aimed to evaluate the composition, abundance, species richness and seasonal distribution of sand flies in the region and to determine the constancy of the insect population.

Methods

The survey was conducted at three sites located in the municipalities of Barreirinhas and Santo Amaro between September 2012 and August 2013. Sampling was performed monthly using automatic light traps installed 1.5 m above the soil adjacent to 13 randomly selected rural dwellings. At each site, one trap was placed in the peridomicile near to animal enclosures and another (extradomicile) at 500 m from the peridomicile.

Results

A total of 4,474 individual sand flies were collected over the year with the highest abundance recorded during the rainy season (December to June). Nine species were collected: L. whitmani, L. longipalpis, L. lenti, L. sordellii, L. evandroi, L. flaviscutellata, L. wellcomei, L. termitophila and L. intermedia. Although peridomiciliary and extradomiciliary environments presented similar species richness, the Shannon diversity index was significantly lower in the former (H’ = 2.4) compared with the latter (H’ = 4.98). Lutzomyia whitmani and L. longipalpis were the most abundant species and were classified as constant (constancy index, CI = 100 %) along with L. lenti (CI = 58.3), L. evandroi (CI = 58.3) and L. sordellii (CI = 66.7). The remaining four species presented CI values between 25 and 50 % and were considered accessory.

Conclusions

The present results confirm the present of L. whitmani and L. longipalpis in the peridomicile of houses in Lençóis National Park. The abundance of these species could explain, respectively, the endemicity of cutaneous leishmaniasis and sporadic cases of visceral leishmaniasis in the study area. However, in the case of cutaneous leishmaniasis, the presence of other sand fly vectors (in addition to L. whitmani) cannot be neglected. Finally, this study emphasizes the need for a more effective and permanent supervision to control the expansion of these vectors and leishmaniasis outbreaks.

Ecological aspects and molecular detection of Leishmania DNA Ross (Kinetoplastida: Trypanosomatidae) in phlebotomine sandflies (Diptera: Psychodidae) in terra firme and várzea environments in the Middle Solimões Region, Amazonas State, Brazil

Background

Phlebotomine sand flies (Diptera: Psychodidae) are insects of medical importance due to the role that some species play in the transmission of leishmaniasis. This work aimed to study some ecological aspects among sand flies fauna inhabiting two different environments: the várzea (lowland Amazonian forest) and terra firme (upland Amazonian forest), both located in Tefé Municipality, Amazonas State, Braziland to detect Leishmania infection in those phlebotomine populations.

Methods

Sand flies were collected using HP light traps. Collection took place over the course of six months: January, February, April, August, September, and October of 2013. To detect natural infection by Leishmania, DNA samples were extracted from female sand flies and submitted to Polymerase Chain Reaction (PCR) targeting the kDNA gene; Leishmania species were identified by PCR-RFLP targeting the hsp70 gene and genetic sequencing.

Results

In all, 5,716 individuals were collected, and 46 species were identified. Trichophoromyia ubiquitalis (3,330 – 58.26%) and Nyssomyia antunesi (661 – 11.26%) were the most abundant species. Species richness was greater in terra firme environments (42 species) than in the várzea environments (22 species), and forests ecotopes (43 species) were richer than peridomiciles (28 species). DNA of Leishmania was found in Th. ubiquitalis and Psychodopygus davisi, both of which inhabit the terra firme environment and sequencing analysis confirmed the presence of Leishmania (Viannia) lainsoni DNA in Th. ubiquitalis in Tefé Municipality.

Conclusions

The high abundance of Th. ubiquitalis and Ps. davisi and detection of DNA of Leishmania sp. may indicate that both species could be putative vectors for American Cutaneous Leishmaniasis (ACL) in the terra firme environment of Tefé. The sand fly fauna found in várzea is rich and diverse, exhibiting several species, nevertheless the seasonal hydric stress during part of the year that could influence the local diversity, if compared with other studies. This is the first report in Amazonas State of Th. ubiquitalis with presence of L. (V.) lainsoni DNA.