Sand Fly Fauna Research Articles

Sandfly fauna and ecological analysis of Phlebotomus orientalis and Phlebotomus martini in the lowland foci of visceral leishmaniasis in Somali Regional State, southeast Ethiopia

Objective: To identify the sandfly fauna and analyze ecology of sandfly vector(s) of visceral leishmaniasis in three districts of Somali Regional State, southeast Ethiopia. Methods: Sandflies were collected from four sampling habitats, including indoor, peri-domestic, farm field and mixed forest using light and sticky traps in July 2016, and February and April 2017 in Liben and Dawa zones in the Somali Regional State, southeastern Ethiopia. Results: In total, 4 367 sandfly specimens, belonging to 12 species (three Phlebotomus spp. and nine Sergentomyia spp.) were identified. Phlebotomus (P.) heischi, P. orientalis, and P. martini constituted 45.7%, 31.1%, and 23.1% of the sandfly collection, respectively. There were significant differences in the median number of P. orientalis, and P. martini captured per CDC trap/night between the three sampling districts (P Conclusions: The study demonstrated that the presence of P. orientalis and P. martini are probable vectors of visceral leishmaniasis in this new focus. The findings of our study will improve the understanding of the dynamics of visceral leishmaniasis transmission and will facilitate the implementation of integrated disease control measures based on ecological knowledge of visceral leishmaniasis vector in Liben and Dawa zones and its surrounding regions.

An overview of the sandfly fauna (Diptera: Psychodidae) followed by the detection of Leishmania DNA and blood meal identification in the state of Acre, Amazonian Brazil.

BACKGROUND In Acre state, Brazil, the dissemination of cutaneous leishmaniasis has increased in recent years, with limited knowledge of the potential Leishmania spp. vectors involved.OBJECTIVES Here, data concerning the sandfly fauna of Brasiléia municipality, Leishmania DNA-detection rates and the identification of blood meal sources of insects captured in 2013-2015 are presented. METHODS Parasite detection in female sandflies was performed individually by multiplex polymerase chain reaction (PCR) (Leishmania kDNA/sandfly cacophony-gene), with the identification of Leishmania spp. by hsp70-PCR and sequencing. The identification of blood gut-content from fed females was performed by cyt b-PCR and sequencing. FINDINGS A total of 4,473 sandflies were captured. A subgroup of 864 non-blood-fed females evaluated for the presence of Leishmania DNA showed 2.9% positivity for Leishmania (Viannia) braziliensis and L. (V.) guyanensis. The identification of blood meal sources was performed in 96 blood-fed females, allowing the identification of 13 vertebrate species. In nine/96 fed females, DNA from L. (V.) shawi, L. (V.) guyanensis, L. (V.) braziliensis and Endotrypanum sp. was detected. MAIN CONCLUSIONS In Brumptomyia sp. and Evandromyia termitophila, the first report of Leishmania DNA-detection is provided in Acre; Nyssomyia shawi is implicated as potential vector of L. (V.) braziliensis and L. (V.) guyanensis for the first time in Brazil.

Two new phlebotomine sandfly species (Diptera: Psychodidae) from the Highlands of Madagascar

The Malagasy phlebotomine sandfly fauna includes 17 species: five belong to the genus Phlebotomus, ten to the genus Sergentomyia, and two to the genus Grassomyia. The current article describes Sergentomyia brunhesi sp. nov. and Sergentomyia vistellei sp. nov. from the Malagasy Highlands. Females were described morphologically from specimens collected at Ranomafana–Ifanadiana and Andringitra. Partial molecular sequences of cyt b and 28S rDNA were retrieved for Se. vistellei sp. nov. Waiting new data, we consider these species as ungrouped Sergentomyia. Two new species of Sergentomyia are recorded at higher altitudes in Madagascar. Knowledge of local Biodiversity is increasing. New investigations have to be carried out to describe males, to understand their bionomics, and to identify other potential new species at higher altitudes.

Biodiversity of Hematophagous Diptera (Culicidae and Psychodidae) in a Small Hydroelectric Power Station and Surrounding Area in the State of Minas Gerais, Brazil.

Hydroelectric power stations may affect the population dynamics of mosquitoes and sand flies, a group with impact on public health due to the possibility to transmit pathogens to humans. This work characterized and compared the fauna of mosquitoes and sand flies in a hydroelectric power station and peridomicile areas in the State of Minas Gerais, Brazil. Insect collections were performed in August 2015 at dry season and February 2016 in rainy season. Ten HP light traps were set at each of two sites for three consecutive days in each of two seasons (dry and rainy). Furthermore, collections with Shannon traps were made in each sampling area (hydropower plant and peridomicile area) from 4:00 p.m. being shut down at 8:00 p.m. for two consecutive days in each of two seasons (dry and rainy). In total, 1,222 insects from 13 genera and 27 species were collected. The most plentiful species were respectively Culex declarator (Dyar and Knab, 1906) and Pintomyia pessoai (Coutinho & Barretto, 1940). A high number of insects (78.5%) were collected during the rainy period (P < 0.05). About equitability, statistical significance was observed in the peridomicile area (dry season J = 0.75 and rainy season J = 0.82). The highest values of species diversity were observed in the hydropower plant (H = 2.68) and peridomicile area (H = 2.38) both in the rainy season with statistical significance comparing with dry season. Our results demonstrate that the occurrence of vector species in this region increases the potential risk of transmission of pathogens, especially arbovirus and Leishmania Ross, 1903.

Natural infection by Leishmania infantum in the Lutzomyia longipalpis population of an endemic coastal area to visceral leishmaniasis in Brazil is not associated with bioclimatic factors.

Visceral leishmaniasis (VL) is a zoonosis caused by the protozoan Leishmania infantum and in Brazil is transmitted mainly by the bite of Lutzomuyia longipalpis sand flies. Data about the presence, distribution, natural infection rate, seasonal and monthly dynamics of the vector population are important for optimizing the measures to control VL in endemic areas. This study aimed to identify sand fly fauna in an endemic area for VL to detect the prevalence of L. infantum infection in the Lu. longipalpis population and to elucidate the influence of bioclimatic factors on the monthly fluctuations of this vector. HP light traps were monthly set in the intradomicile and peridomicile of residences located in the central and beachfront areas of Camaçari, a VL endemic area. The sand fly collection was conducted in two periods: i) period 1—between December 2011 and November 2012 and ii) period 2—August 2014 and July 2015. Sand fly species were identified and detection of L. infantum infection by qPCR was performed in pools of female Lu. longipalpis. For the first time, the parasite load of positive pools was correlated with the number of Lu. longipalpis captured per month in both periods. Correlation analyses between the monthly fluctuation of the sand fly population and bioclimatic indices of the municipality in both collection periods were also performed. In both evaluated periods, more than 98% of the collected sand flies were Lu. longipalpis, confirming the predominance of this species in the region. It was captured mostly in the beachfront area in all months evaluated (99%). For the period 1, Leishmania DNA was detected in 81% of tested pools representing a minimal infection rate of 9.6%. In the period 2, 40% of the pools were positive with a minimal infection rate of 10.2%. Infected sand flies were only detected in the beachfront area in both periods. The parasite load was low and did not vary in the evaluated months despite the number of collected sand flies. No correlation was observed for climatic factors in both areas of Camaçari. These findings emphasize the high risk of Leishmania transmission in Camaçari regardless of the season and that other factors, aside from bioclimatic elements, are influencing the sand fly population monthly fluctuation.

Revision of the species composition and distribution of Turkish sand flies using DNA barcodes

BackgroundCurrently, knowledge regarding the phlebotomine sand fly (Diptera: Psychodidae) fauna of Turkey is restricted to regions with endemic leishmaniasis. However, rapidly changing environmental and social conditions highlight concerns on the possible future expansion of sand fly-borne diseases in Turkey, promoting risk assessment through biosurveillance activities in non-endemic regions. Traditional morphological approaches are complicated by extensive cryptic speciation in sand flies, thus integrated studies utilizing DNA markers are becoming increasingly important for correct sand fly identification. This study contributes to the knowledge of the sand fly fauna in understudied regions of Turkey, and provides an extensive DNA barcode reference library of expertly identified Turkish sand fly species for the first time.MethodsFly sampling was conducted at 101 locations from 29 provinces, covering all three biogeographical regions of Turkey. Specimens were morphologically identified using available keys. Cytochrome c oxidase I (cox1) barcode sequences were analyzed both for morphologically distinct species and those specimens with cryptic identity. A taxon identity tree was obtained using Neighbor Joining (NJ) analysis. Species boundaries among closely related taxa evaluated using ABGD, Maximum Likelihood (ML) and haplotype network analyses. Sand fly richness of all three biogeographical regions were compared using nonparametric species richness estimators.ResultsA total of 729 barcode sequences (including representatives of all previously reported subgenera) were obtained from a total of 9642 sand fly specimens collected in Turkey. Specimens belonging to the same species or species complex clustered together in the NJ tree, regardless of their geographical origin. The species delimitation methods revealed the existence of 33 MOTUs, increasing the previously reported 28 recorded sand fly species by 17.8%. The richest sand fly diversity was determined in Anatolia, followed by the Mediterranean, and then the Black Sea regions of the country.ConclusionsA comprehensive cox1 reference library is provided for the sand fly species of Turkey, including the proposed novel taxa discovered herein. Our results have epidemiological significance exposing extensive distributions of proven and suspected sand fly vectors in Turkey, including those areas currently regarded as non-endemic for sand fly-borne disease.

A survey of sand flies (Diptera, Phlebotominae) along recurrent transit routes in Serbia

Serbia was a country endemic for leishmaniasis with rich and abundant sand fly fauna during the middle of the 20th century. After 1968, the disease was considered as eradicated, and as a consequence, all research on vectors and pathogens was neglected. The recent detection of Leishmania infantum in sand flies and confirmed cases of leishmaniasis in humans and dogs indicated the risk of re-emergence in Serbia. Also, for millions of refugees/immigrants, Serbia is a transit route between East-Mediterranean and Middle-East countries, and Central/North Europe, and it is under constant risk of vector and disease introduction.Primary objectives of this research were to determine which sand fly species are present around transit routes, whether they include vectors of the Leishmania spp. moreover, is/are Leishmania spp. present in the vectors.Surveys were conducted at 55 locations, organised in four clusters, which covered main immigrant routes and shelters/camps as well as tourist/trade transit routes. In total, 367 sand fly specimens were collected. Nine species were identified: Phlebotomus papatasi, P. perfiliewi, P. tobbi, P. neglectus, P. sergenti, P. alexandri, P. simici, P. balcanicus and P. mascittii. Detection of P. alexandri represents the first record in Serbia. The diversity of sand fly species increased while the number of collected specimens per night decreased during the period of research neglection. Phlebotomus neglectus, a proven vector of L. infantum, was a predominant species in all surveyed clusters, and in 56,52% of locations, it was the only species present. Although all detected species are regarded either as proven or suspected vectors of Leishmania spp., screening of females for Leishmania presence resulted negative.Our study provides insight into the significant changes of sand fly fauna in Serbia during the end of XX and beginning of XXI century. Diverse sand fly fauna in Serbia suggests that the establishment of new leishmaniasis foci is possible.

A morphotaxonomic album of phlebotomine sand flies (Diptera: Psychodidae) of Egypt

Leishmaniases are endemic in Egypt. The sand fly vectors have been incriminated. An album for the sand fly fauna was based on slide-mounted specimens from the archive of the Research and Training Center on Vectors of Diseases, Ain Shams University, Cairo, Egypt. The sand fly specimens originated from several surveys conducted in different parts of Egypt over 20 years. The album presented twenty species of the genera Phlebotomus and Sergentomyia. These were presented in 68 photos in 18 plates. Nine species of the genus Phlebotomus were reported P. papatasi, P. bergeroti, P. langeroni, P. orientalis, P. major, P. arabicus, P. kazeruni, P. sergenti and P. alexandri and eleven of the genus Sergentomyia, S. squamipleuris, S. palestinensis, S. fallax, S. cincta, S. schwetzi, S. taizi, S. theodori, S. tiberiadis, S. christophersi, S. clydei and S. adleri.

Molecular detection of Leishmania spp in Lutzomyia longipalpis in the city of Lavras, Minas Gerais, Brazil

Leishmaniasis is a neglected disease that affects a large part of the world population. Knowing the sand fly fauna of a region is of fundamental importance for guiding health surveillance actions related to the prevention and control of leishmaniasis. A total of 86 specimens of sand flies (60 females and 26 males) were collected. Using the classification proposed by Galati (2003), the following species were identified: Lutzomyia longipalpis (Lutz & Neiva, 1912), Migonemyia migonei (França, 1920), Evandromyia cortelezzi (Brethes, 1923), Ev. sallesi (Galvão & Coutinho, 1939), Nyssomyia whitmani (Atunes & Coutinho, 1939), Psathyromyia lutziana (Costa Lima, 1932), Ev. lenti (Mangabeira, 1938), Brumptomyia sp. (França and Parrot, 1921), and Pressatia sp. (Mangabeira, 1942). Using PCR with internal transcribed spacer target to identify infected sand flies, five Lu. longipalpis females were infected with Leishmania spp. Despite the small number of specimens collected, considerable species diversity was found in the study area.

Composition and Vertical Stratification of Phlebotomine Sand Fly Fauna and the Molecular Detection of Leishmania in Forested Areas in Rondônia State Municipalities, Western Amazon, Brazil.

This study examined sand fly diversity and the natural infection of sand flies by Leishmania in three localities in Rondônia State: Santo Antônio and São Vicente farm, which are anthropized environments, and the Jamari FLONA, which has not been anthropized. Sand flies were collected in canopies and at ground level using CDC light traps and BG-Sentinel CO2 traps. Female sand flies were grouped into pools that were subjected to DNA extraction and the samples were subjected to PCR to detect and identify Leishmania. A total of 6696 specimens were examined and 52 species were identified. Abundance was greater in canopies than at ground level (n = 5657 and n = 1039, respectively); however, fauna composition was more diverse at ground level. A total of 4870 specimens were collected using CDC light traps and 1826 specimens were collected using BG-Sentinel traps. The presence of Leishmania DNA was detected in 12 pools, and Leishmania species profiles were identified in three of these pools: one pool of Psychodopygus amazonensis and one pool of Psychodopygus chagasi infected with Le. (Vi.) braziliensis, and one pool of Psychodopygus davisi infected with Le. (Le.) amazonensis. Sand flies are sensitive to environmental modification and species diversity is greater in regions that have experienced less anthropization. Although the annual infection rate of cutaneous leishmaniasis is high in Rondônia State, the role that sand flies play in the leishmaniasis transmission cycle remains poorly understood. The high abundance of Ps. davisi and Trichophoromyia auraensis and the presence in these species of natural infection by Leishmania spp. suggest that these species are acting as vectors of tegumentary leishmaniasis in Rondônia.

Vector and reservoir surveillance study in a canine and human leishmaniasis endemic area in most western part of Turkey, Karaburun

Leishmaniasis is an arthropod borne disease that is endemic in 102 countries and one and half million new cases are reported each year. Sand flies are the one and only proven vectors of the disease and dogs are the main reservoirs in urban areas. Karaburun peninsula is located in most western part of Turkey and is reported to be an endemic area for human and canine leishmaniasis. The most recent study was undertaken more than 15 years ago in The peninsula and no clear data available for vectors or reservoirs. Thus, we aimed to update the information regarding sand fly diversity, infection status of reservoirs and vectors in the study area.Sand flies were collected using CDC light traps at 13 different sites of Karaburun and species identification was made using previously published keys. Monospecific pools were generated using midguts with blood retention and were screened for the presence of Leishmania spp. DNA by molecular techniques. A non-invasive conjunctival swab sampling was performed to identify the infection status among reservoirs and species typing of the causative agent was also undertaken using ITS1 PCR.Three out of 30 pools were found positive for Leishmania infantum that were generated using guts of Phlebotomus tobbi (n:36). Among all sampled dogs (44) and cats (19), 11 and one of them were found positive for L. infantum, respectively. There was a decrease in the number of P. papatasi during the study period, while increase was observed in the number of P. tobbi.The presence of proven vectors and reservoirs as well as Leishmania DNA in cats was shown in the present study. Sand fly fauna is updated and Leishmania DNA presence in cats was reported in the study area for the first time.

Presence ofSergentomyia(Parrotomyia)lewisi(Diptera: Psychodidae) in Tunisia

In Tunisia, 17 phlebotomine sand fly species are reported, belonging to genera Phlebotomus and Sergentomyia. However, subsequent to faunal studies and outbreaks of leishmaniasis in different regions of the country, unrecognized sand fly species could exist. Indeed, we report in this study the presence of Sergentomyia (Parrotomyia) lewisiParrot 1948. A brief collection of phlebotomine sand flies was undertaken in August 2016 in Khbina locality, in Sidi Bouzid governorate situated in Central Tunisia, which constitutes an old focus of Zoonotic Cutaneous Leishmaniasis. Sand flies were collected, using CDC light traps that were placed overnight, in different biotopes (inside habitations, outdoors, and within animal shelters). Specimens were collected and morphologically identified. Measurements were taken with an ocular micrometer. Two female specimens of the species Se. (Parrotomyia) lewisi were collected. One specimen is here described and measured. A comparison of its taxonomic characters to the holotype from Sudan and a specimen from Algeria is also presented. This species was until now only reported from Sudan, Ethiopia, Algeria, and Morocco. It is here described for the first time in Tunisia, which raises the Tunisian sand fly fauna to seven subgenera and 18 species.

Sand fly fauna (Diptera: Psychodidae) from Serra da Mocidade Nacional Park: report of vectors and putative vectors of American cutaneous leishmaniasis and new records for the state of Roraima, Brazil.

Phlebotomine sand flies are insects of medical importance, as they are vectors of viruses, bacteria and trypanosomatids of the genus Leishmania Ross, the causative agent of leishmaniasis (Forattini 1973). During the past 20 years approximately 500,000 cases of leishmaniasis have been reported in Brazil. Most of these cases were reported in the North and Northeast regions. In the State of Roraima, almost 2,000 cases, including both cutaneous leishmaniasis (CL) and visceral leishmaniasis (VL), have been reported during the past three years (SINAN 2017). Usually the transmission by infected female sand flies occurs in wild or rural areas, but there have also been recorded cases and vector captures in urban environments. Some sand fly species are known to enter houses in search of resting places and blood meal sources; as a result of this behavior, they are remarkably adaptable to new environments (Carvalhoet al. 2010).

Richness and Diversity of Phlebotomine Sand Flies (Diptera: Psychodidae) in North Khorasan Province, Northeast of Iran

We aimed to determine the species composition, richness and diversity indices of the Phlebotomine sand flies at different topographic condition in visceral (VL) and cutaneous leishmaniasis (CL) foci in the northeast of Iran. This cross-sectional study was conducted during 2016 in North Khorasan Province. The sampling was focused on rural regions, where human cases of VL and/or CL were diagnosed and reported during last 5 years. Sand flies were collected three times each twenty days during peak periods of seasonal activity. Seven collection methods were used. Some Alpha and Beta diversity indices were calculated. Overall, 7253 sand flies were collected and identified. They were from 19 species of Phlebotominae sand-flies. Phlebotomus sergenti and Ph. papatasi were the most prevalent (84.9%) species in the study area. Species richness (S) was very different in three areas and were18, 8, and 4 respectively but Evenness (E) were 0.357, 0.345, and 0.380, so evenness was almost equal in the study areas. Shannon Index (H) and Margalef Richness Index were calculated 1.033, 0.718, 0.527 and 2.117, 0.8998, 0.4006 respectively. The sand fly fauna in North Khorasan Province was very rich and often included some of the most important proven or suspected vectors of leishmaniasis. Species diversity indices (Shannon index, and Simpson's index) were not high due to decreasing in evenness. The Margalef richness index could accurately reflect the biodiversity of sand flies between three subtidal locations.

VALIDATION OF PHLEBOTOMINE CARDINAL TEMPERATURES AND HUMIDITIES IN THE REGION OF RIO ARINOS, MATO GROSSO, BRAZIL

The purpose of this study was to validate the phlebotomine cardinal temperatures and humidities, reported by Campelo Junior et al. (2014), using different collection data, obtained in a study on the number of these insects, captured in the Arinos region, in Nova Mutum, Mato Grosso, Brazil, according to spatial (100 m to 1000 m) and temporal (June 2011 to April 2012) variability. Phlebotomines were captured in the riparian forest, by means of 10 traps positioned approximately every 100 m, northwards from the road along the river bank, with samples obtained bimonthly during three consecutive nights for a period of 12 months. Average relative humidity and temperature during the periods when the traps remained at the collection points were measured using a digital thermometer-hygrometer. The phlebotomine sand fly fauna was highly diversified, presenting 31 species, of which Lutzomyia antunesi was the most prevalent (45.4%). L. flaviscutellata, L. whitmani and L. umbratilis, known vectors of Leishmania spp., were also found. There was a marked variation in the quantity of phlebotomines captured throughout the consecutive collection days, as each sampling was affected by different factors determining a different maximum value for the number of insects present in each situation, as demonstrated for temperature and air humidity.

Disney Trap Attractiveness for the Cortelezzii Series (Diptera: Psychodidae, Phlebotominae) in a Fishing Tourism Area, Bonito Municipality, Mato Grosso do Sul State, Brazil.

Sand fly fauna is frequently sampled using automatic light or Shannon traps, yet few studies have been devoted to investigating the effectiveness of Disney traps baited with live animals as an attractant. This study sought to identify the phlebotomine fauna attracted to Disney traps having hamsters (Mesocricetus auratus) as bait. A hamster-baited Disney trap was installed in a gallery forest located in Águas do Miranda District, Bonito Municipality, Mato Grosso do Sul state, Brazil, from November 2011 to October 2012. A total of 717 phlebotomines were collected, in which male (251) and female (463) specimens of the Cortelezzii series (Diptera: Psychodidae) predominated (99%). Males were attracted from January to July, whereas the females were predominantly attracted from January to May. No significant correlation was observed between the monthly climatic averages of temperature, rains and humidity, and the numbers of insects collected. Although these findings showed the attractiveness of both sexes of the species of the Cortelezzii series to golden hamsters, further studies are needed to investigate the blood meal preferences of these females to other rodents. As rodents have been reported as reservoirs of Leishmania spp. (Kinetoplastida: Trypanosomatidae), research using live-baited traps can reveal feeding preferences of sand flies and the importance of various rodent species in the zoonotic cycle.

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.

Multiplex Polymerase Chain Reaction for Detection of Leishmania Sp. in Sandflies of the Paraná River Islands, Southern Brazil.

Leishmaniases are classified as tegumentary leishmaniasis (TL) and visceral leishmaniasis (VL). Brazil is among the countries with the highest number of TL and VL cases. This study was undertaken to standardize the multiplex polymerase chain reaction (PCR) for the detection of the genus Leishmania in sandflies of endemic regions, on islands in the Upper Paraná River, northwestern Paraná. The sandflies were collected on 10 islands, from November 2012 to November 2014, with Falcão light traps, identified and conserved in tubes containing isopropanol, for subsequent DNA extraction. Two pairs of primers were used for multiplex PCR: A1/A2 and 5Llcac/3Llcac. Nyssomyia neivai was the predominant species of the collected specimens. A total of 3870 samples of female sandflies were analyzed and submitted to multiplex PCR, for the validation of the technique. All pools showed the 220 bp fragment for sandfly DNA detection, but no ∼120 bp fragment of Leishmania DNA was found. Although no natural infection of Ny. neivai by Leishmania was found in this study, the interaction of sandflies with Leishmania and its natural reservoirs continues in these Paraná River islands, despite the low diversity of the sandfly fauna. Some of these islands have permanent residents and are frequented by tourists.

Phlebotomine sand flies (Diptera: Psychodidae) in the Greek Aegean Islands: ecological approaches

BackgroundBlood-sucking phlebotomine sand flies are the vectors of the protozoan parasites Leishmania spp. Different Phlebotomus species transmit different Leishmania species causing leishmaniases which are neglected diseases emerging/reemerging in new regions. Thirteen sand fly species, ten belonging to the medically important genus Phlebotomus and three belonging to Sergentomyia are known in Greece. An increasing number of human and dog cases are reported each year from all parts of the country including the Aegean Islands. However, no previous study has been conducted on the sand fly fauna on the islands, except for Rhodes and Samos. The aim of this study was to investigate sand fly species in eleven small Aegean islands; to understand species-specific relationships with environmental and climatic factors and to compare sand fly community parameters among islands. A risk analysis was carried out for each species using climatic and environmental variables.ResultsNine sand fly species: Phlebotomus neglectus, P. tobbi, P. similis, P. simici, P. perfiliewi, P. alexandri, P. papatasi, Sergentomyia minuta and S. dentata, were collected from the islands studied. Phlebotomus (Adlerius) sp. and Sergentomyia sp. specimens were also collected but not identified to the species level. There was a positive effect of distance from the sea on the abundance of P. neglectus, S. minuta and S. dentata, and a negative effect on the abundance of P. tobbi, P. simici and P. similis. In general, temperature preferences of sand fly populations were between 21 and 29 °C. Nevertheless, there were significant differences in terms of temperature and relative humidity preference ranges among species. The most important species found, P. neglectus, was indisputably the most adapted species in the study area with a very high reaction norm, favoring even the lower temperature and humidity ranges. Overall, the sand fly fauna in the islands was very rich but there were differences in species diversity, as indicated by the values of the Shannon-Wiener index, along with evenness and richness of the sand fly fauna between the islands and altitude ranges in the islands.ConclusionsThe study indicated that the Greek Aegean Islands, however small, maintain a rich sand fly fauna. This includes important vectors of Leishmania spp. representing a risk for parasite transmission to humans and dogs along with the danger of maintaining new Leishmania spp. if introduced to the area.

Ecology, feeding and natural infection by Leishmania spp. of phlebotomine sand flies in an area of high incidence of American tegumentary leishmaniasis in the municipality of Rio Branco, Acre, Brazil

BackgroundPhlebotomine sand flies (Diptera: Psychodidae) are insects of medical importance due to their involvement in the zoonotic transmission of Leishmania spp. to vertebrates. The aim of this work was to study the ecology of the sand fly fauna of two types of environments, a rural environment (the Transacreana Road) and an urban park (Horto Florestal Park), both located in the municipality of Rio Branco in the state of Acre, Brazil. Additionally, this study intended to investigate Leishmania infection and blood meal sources of these sand flies using molecular techniques.MethodsThe sand fly fauna was studied in different environments (i.e. forest and peridomestic environments in a rural area, and an urban forest) using Shannon traps and HP light traps to collect sand fly specimens over 13 consecutive months (December 2014 to January 2016). For investigating natural infection by Leishmania and the source of sand fly blood meals, DNA samples were extracted from female sand flies and subjected to polymerase chain reaction targeting ITS1 and cytb genes. DNA sequencing was subsequently used to identify species of Leishmania and the source of blood meals.ResultsA total of 2515 individual sand flies of 43 species were collected and identified, Trichophoromyia auraensis (839; 33.35%), Trichophoromyia spp. (537; 21.35%) and Evandromyia saulensis (187; 7.43%) were more abundant in the rural area (S = 41 species) than in the urban forest. No significant differences were found in species richness between forest and peridomestic environments in the rural area (H = 0.04; P > 0.05), but a larger number of species was found in the forest. Leishmania DNA was sequenced in 13 samples, confirming the presence of L. (V.) braziliensis in Th. auraensis (n = 1), Ev. saulensis (n = 2), Ev. walkeri (n = 1), Ps. llanosmartinsi (n = 1), Pi. nevesi (n = 2), Ps. davisi (n = 1), Ps. ayrozai (n = 1), Pa. aragaoi (n = 1), Ny. antunesi (n = 1) and Ev. infraspinosa (n = 1). Only Ps. ayrozai possessed a sequence similar to that of L. (V.) guyanensis (99%). Through microscopic analysis, five specimens of Ev. saulensis were found to possess flagellate forms in the hindgut, with an infection rate of 2.4%. Samples from 33 fed females were submitted to cytb gene amplification, for which sequencing determined that all were similar to the sequence deposited on GenBank for Gallus gallus (domestic chicken).ConclusionsThe high abundance of Trichophoromyia auraensis and Ev. saulensis, and the detection of L. (V.) braziliensis DNA, suggests that both species may be vectors of American tegumentary leishmaniasis. Psychodopygus ayrozai was found to be infected by L. (V) braziliesnsis and L. (V.) guyanensis, and although collected in low abundance, it may be a potential vector in the region. The sand fly fauna was found to be rich and diverse with predominance of the genus Psychodopygus. Identification of food sources of fed females showed that 100% amplified a gene region compatible with the domestic chicken, which although considered refractory in the disease transmission cycle, may have an influence on the population dynamics of sand flies.