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1.
Arch Microbiol ; 205(2): 64, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36633698

RESUMO

Phlebotomine sand flies (Diptera: Psychodidae) are the proven vectors of Leishmaniases which are widespread parasitosis in many tropical and subtropical countries. The development of infective metacyclic Leishmania (Kinetoplastida: Trypanosomatidae) promastigotes stage is restricted to the vector midgut. Recently, several studies have assessed the influence of the sand fly midgut fungal microflora on the development of invective Leishmania stage. The aim of this study was to identify the fungal microflora from the cuticle and midgut of wild caught sandflies. A total of 50 sandflies were caught in two different leishmaniasis foci of center Tunisia and analyzed using an in vitro isolation of fungi followed by a morphological and molecular identification of fungal isolates. The morphological identification of sandflies specimens revealed five Species: Phlebotomus (P.) papatasi (n = 25), P. perniciosus (n = 15) P. riouxi (n = 6), P. longicuspis (n = 3) and P. sergenti (n = 1). Forty positive fungal cultures were isolated from 34 sand flies (19 males and 15 females) distributed as following: P. papatasi (n = 16), P. perniciosus (n = 11), P. riouxi (n = 4), P. longicuspis (n = 2) and P. sergenti (n = 1). Thirty-five cultures were isolated from the cuticles and five from the guts. A total of 15 fungi genera belonging to 8 families were identified with the predominance of Aspergillus genus followed by Penicillium genus. Among the 15 fungi genera, five were common between males and females specimens. Lecytophora canina and Leishmania major co-infection was detected in the gut of a female P. papatasi. Our preliminary findings highlight the high diversity of fungal microflora from the sand flies midguts.


Assuntos
Leishmaniose , Phlebotomus , Psychodidae , Feminino , Masculino , Animais , Tunísia
2.
Viruses ; 15(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36680189

RESUMO

The continuously expanding distribution of sand flies, proven vectors of Leishmania and of several phleboviruses, is a growing public health issue in Europe. Especially in Italy, visceral leishmaniasis (VL) is occurring with increasing incidence northward, in previously non-endemic provinces. Around the globe, disease elimination efforts largely focus on sand fly vector insecticidal control, often leading to the development of resistance. In Emilia-Romagna (ER), northern Italy, insecticides are heavily applied for agricultural and mosquito control, but not specifically against sand flies. Here, we investigated the sand fly species composition in certain environmental settings in ER provinces and monitored the presence of pyrethroid resistance mutations and pathogen circulation. Phlebotomus perfiliewi, a dominant vector of Leishmania infantum, was detected almost exclusively in the region. No mutations in the voltage-gated sodium channel gene, e.g., knock-down resistance mutations I1011M, L1014F/S, V1016G, or F1020S, were recorded. Pathogen monitoring revealed that almost 40% of the tested sand fly pools were positive for Leishmania, while the presence of Toscana and Fermo phleboviruses was also observed in much lower frequencies (≤3% positive pools). Regular epidemiological and entomological monitoring, alongside resistance surveillance, is highly recommended to ensure the sustainability and efficiency of vector control interventions.


Assuntos
Inseticidas , Leishmania infantum , Leishmaniose , Phlebotomus , Phlebovirus , Psychodidae , Animais , Resistência a Inseticidas/genética , Phlebotomus/genética , Leishmania infantum/genética , Inseticidas/farmacologia , Itália/epidemiologia
3.
Acta Trop ; 238: 106798, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36529191

RESUMO

The accurate identification of sandfly species is crucial because some species transmit medically significant diseases, including leishmaniasis, bartonellosis and sandfly fever. However, due to the high similarity of the external morphology in sandfly species, identification can only be performed using internal morphological characteristics after dissection, which is time consuming and requires highly experienced staff. Thus, the introduction of suitable molecular markers may solve these identification problems. This study screened suitable DNA barcodes to identify common sandfly species in China. The phlebotomine sandflies were collected from Sichuan, Henan and Hainan Provinces from 2014 to 2016. The species were identified by the morphological characteristics of the pharyngeal armature and spermatheca. The genomic DNA of sandfly was extracted individually, and mitochondrial DNA (mtDNA) cytochrome C oxidase subunit I (COI) and cytochrome B (Cytb) as well as the 18S subunit of ribosomal DNA (rDNA) were amplified using polymerase chain reaction (PCR). Additionally, intraspecific and interspecific differences (p-distance) were calculated to evaluate the feasibility of the three gene fragments as a DNA barcode. The phylogeny trees of all sandfly species in this study were constructed using neighbor joining (NJ) method. Six species were identified by the morphological features, belonging to Phlebotomus and Sergentomyia, as Ph. chinensis s. l., Ph. stantoni, Se. bailyi, Se. iyengari, Se. squamirostris, and Se. squamipleuris. Analysis based on three gene fragments revealed some degree of intraspecific polymorphism among these sandfly species in China. The largest intraspecific variation occurred in Ph. chinensis s. l. (mtDNA COI, p-distance = 0.042; mtDNA Cytb, p-distance = 0.071), but the 18S rDNA fragment showed a small variation (p-distance = 0.005). The ranges of interspecific p-distances for mtDNA COI and mtDNA Cytb were 0.138 - 0.231 and 0.128 - 0.274, respectively. However, the interspecific p-distances of 18S rDNA are relatively low ranging from 0.003 to 0.055. Both mitochondrial COI and Cytb gene fragments are valid molecular identification markers in theses sandfly species. The topological structure of phylogeny trees based on mtDNA COI, mtDNA Cytb and 18S rDNA genes were all consistent with morphological classification. And we also found there were significant intraspecies differences within Ph. chinensis s. l. (0.006-0.071) and Se. bailyi (0.002-0.032) based on mtDNA Cytb gene fragment. Sequence alignment data suggested that Ph. chinensis s. l. from Sichuan should be Ph. sichuanensis, and the sandfly specimen collected from Henan was Ph. chinensis s. s.. There could be cryptic species in Se. bailyi from China.


Assuntos
Phlebotomus , Psychodidae , Animais , China , Citocromos b/genética , Código de Barras de DNA Taxonômico/métodos , DNA Mitocondrial/genética , DNA Ribossômico/genética , Filogenia , Psychodidae/genética
4.
Parasitol Res ; 122(2): 671-674, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36567398

RESUMO

Human visceral leishmaniasis (HVL) is a neglected disease that occurs in 98 countries on five continents, and it is endemic in tropical and subtropical regions. In South America, the etiological agent of HVL is Leishmania infantum (syn. Leishmania chagasi), mainly transmitted through the bite of an infected sandfly female from the genus Lutzomyia. In American HVL endemic areas, the occurrence of asymptomatic infection is common, which contributes to the possibility of L. infantum transmission during a blood transfusion. To know the prevalence of L. infantum asymptomatic infection in blood donors from the microregion of Adamantina, we investigated 324 peripheral blood samples from donors through immunofluorescence (IFAT) and PCR-RFLP techniques. Seven blood samples (2.16%) tested positive for Leishmania by IFAT, and from those, six presented positive results by PCR (85.71%), which were later identified as L. infantum by RFLP. The presence of L. infantum in the peripheral blood of blood donors supported the hypothesis of transmission by blood transfusion and points to the need to include tests for visceral leishmaniasis in blood bank screening tests and pre-storage measures, especially in endemic areas to prevent the exponential increase of HVL by blood transfusion.


Assuntos
Leishmania infantum , Leishmaniose Visceral , Psychodidae , Animais , Humanos , Feminino , Leishmania infantum/genética , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Doadores de Sangue , Infecções Assintomáticas , Reação em Cadeia da Polimerase
5.
Acta Trop ; 238: 106807, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36577477

RESUMO

The sand fly Psathyromyia shannoni is a broadly distributed species that is relevant for the transmission of pathogens such as Leishmania, Bartonella and viruses in several countries of America. This species belongs to the Shannoni complex. Yet its identification is difficult due to morphologic intraspecific polymorphisms that make it difficult to distinguish between species, and could therefore lead to misidentification and overestimation of its distribution. The aim of this study was to perform a retrospective study on the genetic diversity of Pa. shannoni based on the Cytochrome Oxidase subunit 1 gene and considering its geographic distribution to achieve a better identification and differentiation from other species of the Shannoni complex. According to the Maximum Likelihood analysis and the data on the genetic structure, we propose a modified delimitation of Pa. shannoni species by classifying it into at least three genetic lineages, based on genetic variability and distribution. However, more genetic information on the COI gene, mainly from countries where this species has been reported, is needed to strengthen this proposal.


Assuntos
Leishmania , Phlebotomus , Psychodidae , Animais , Psychodidae/genética , Psychodidae/anatomia & histologia , Estudos Retrospectivos , Variação Genética
6.
Artigo em Inglês | MEDLINE | ID: mdl-36542015

RESUMO

BACKGROUND: The American cutaneous leishmaniasis (ACL) is expanding in peri-urban environments. METHODS: An entomological survey was conducted in the area of the occurrence of an autochthonous urban case of ACL. Sandflies and a parasitological slide of the human case were submitted for molecular diagnosis. RESULTS: Nyssomyia whitmani and Ny. antunesi were the most frequently collected species. Ny. whitmani and Bichromomyia flaviscutellata were positive for Leishmania guyanensis and L. lainsoni, respectively. The human case tested positive for L. lainsoni. CONCLUSIONS: Sandflies and Leishmania parasites present in urban forest may occur frequently in nearby domiciliary environments; thus, these areas must be monitored.


Assuntos
Leishmania guyanensis , Leishmania , Leishmaniose Cutânea , Psychodidae , Animais , Humanos , Urbanização , Insetos Vetores/parasitologia , Leishmaniose Cutânea/epidemiologia , Psychodidae/parasitologia , Brasil/epidemiologia
7.
Viruses ; 14(12)2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36560697

RESUMO

In Yangquan County, the sandfly-transmitted virus (Wuxiang virus) was first isolated from sandflies in 2018. However, relationships between the abundance and seasonal fluctuations of local sandflies and sandfly-transmitted viruses are unknown. Herein, we report that sandfly specimens were collected in three villages in Yangquan County, from June to August, 2019. A total of 8363 sandflies were collected (June, 7927; July, 428; August, 8). Eighteen virus strains (June, 18; July, 0; August, 0) were isolated in pools of Phlebotomus chinensis. The genome sequence of the newly isolated virus strain was highly similar to that of the Wuxiang virus (WUXV), isolated from sandflies in Yangquan County in 2018. Our results suggested that the sandfly-transmitted viruses, and the local sandfly population, are stable in Yangquan County, and that June is the peak period for the virus carried by sandflies in this area.


Assuntos
Febre por Flebótomos , Phlebotomus , Phlebovirus , Psychodidae , Animais , Phlebovirus/genética , China
8.
ScientificWorldJournal ; 2022: 5098005, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36408197

RESUMO

Leishmaniasis is a parasitosis caused by parasites of the genus Leishmania and is transmitted by Phlebotominae sand flies. An entomological survey was carried out in different localities of Zagora Province. Our work allowed us to establish an inventory of sand flies to study potential vectors of leishmaniasis and to compare the composition and the specific abundance of different endemic stations. The sand flies were collected using CDC miniature light traps during the month of July 2019 in the ten studied villages. The results indicate the presence of thirteen species, belonging to the genera Phlebotomus and Sergentomyia. Phlebotomus papatasi was the predominant species (46.65%) followed by Ph. alexandri (17%), Ph. longicuspis (11.55%), Ph. bergeroti (1.53%) and Ph. sergenti (1.27%). Phlebotomus kazeruni (0.03%) was rare, and only one female was captured in Ifred. Sergentomyia schwetzi (8.69%) was the most prevalent species in the Sergentomyia genus followed closely by Se. fallax (6.84%). Sergentomyia africana was present with a proportion of (3.86%) followed by Se. clydei (1.96%). Sergentomyia dreifussi (0.46%), Se. antennata (0.08%), and Se. minuta (0.08%) were very limited. Phlebotomus papatasi, Ph. alexandri, Ph. bergeroti, Ph. longicuspis, Ph. sergenti, Se. schwetzi, Se. clydei, and Se. fallax are constant species, being present at least in 50% of the stations (occurrence> 50%). Common species (25%-49%) were Se. minuta and Se. africana and rare species were Ph. kazeruni and Se. antennata with a very limited distribution (occurrence <12%). The greatest species richness was found in Ksar Mougni and Ifred with the occurrence of 11 species, but overall, it was high (>9 species) in most of the villages. The Shannon-Wiener index was high (H' > 1) in eight localities (Ksar Mougni, Tassaouante, Bleida, ZaouiteLeftah, Ifred, Timarighine, Ait Oulahyane, and Ait Ali Ouhassou). The high value of this index is in favor of the ZaouiteLeftah locality (Shannon-Wiener index = 1.679) which is explained by the presence of a stand dominated by Ph. papatasi. In order to avoid exposure to infections, a good epidemiological surveillance and vector with rodent control measures must be well maintained. Awareness campaigns are also required and must be conducted for better knowledge of the disease.


Assuntos
Leishmaniose Cutânea , Phlebotomus , Psychodidae , Animais , Feminino , Marrocos/epidemiologia , Insetos Vetores/parasitologia , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Phlebotomus/parasitologia
9.
Parasit Vectors ; 15(1): 412, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335408

RESUMO

Leishmania infections span a range of clinical syndromes and impact humans from many geographic foci, but primarily the world's poorest regions. Transmitted by the bite of a female sand fly, Leishmania infections are increasing with human movement (due to international travel and war) as well as with shifts in vector habitat (due to climate change). Accurate diagnosis of the 20 or so species of Leishmania that infect humans can lead to the successful treatment of infections and, importantly, their prevention through modelling and intervention programs. A multitude of laboratory techniques for the detection of Leishmania have been developed over the past few decades, and although many have drawbacks, several of them show promise, particularly molecular methods like polymerase chain reaction. This review provides an overview of the methods available to diagnostic laboratories, from traditional techniques to the now-preferred molecular techniques, with an emphasis on polymerase chain reaction-based detection and typing methods.


Assuntos
Leishmania , Leishmaniose , Phlebotomus , Psychodidae , Animais , Humanos , Feminino , Leishmaniose/diagnóstico , Leishmania/genética , Reação em Cadeia da Polimerase/métodos
10.
Parasit Vectors ; 15(1): 406, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329517

RESUMO

BACKGROUND: Colombia is ranked very high among countries with the highest numbers of endemic Leishmania species (n = 9) causing human disease. Although much effort has been devoted to generating simple and specific tools for Leishmania species identification, challenges remain in the discrimination of species belonging to the Leishmania (Viannia) guyanensis complex: L. (V.) guyanensis and L. (V.) panamensis. METHODS: A set of seven reference strains of species belonging to the L. (Leishmania) and L. (Viannia) subgenera, clinical strains from human cases of cutaneous leishmaniasis (CL; n = 26) and samples collected from sylvatic mammals and sand flies (n = 7) from endemic areas in Colombia were analyzed in this study. The heat-shock protein 70 gene (hsp70) was amplified by PCR from DNA extracted from logarithmic-phase promastigotes or tissue samples, and the PCR products were sequenced. Sequence alignment was performed against a set of previously published and curated sequences, and phylogenetic analysis based on the maximum-likelihood and Bayesian inference approaches was conducted. Haplotype diversity among strains and species of the L. (V.) guyanensis complex was explored using a median-joining network. RESULTS: Sequencing of the hsp70 gene for L. (Viannia) spp. typing was comparable to species identification using isoenzyme electrophoresis or monoclonal antibodies. Complete species matching was found, except for one sylvatic sample with an identity yet unsolved. Among the L. (V.) panamensis clinical strains, two distinctive phylogenetic clusters were found to correlate with two different zymodemes: L. (V.) panamensis Z2.2 and Z2.3. Analysis of samples from sylvatic environments identified novel records of naturally infected wild mammal and sand fly species. CONCLUSIONS: Our results support the adequacy of hsp70 gene sequencing as a single-locus approach for discrimination of L. (Viannia) spp., as well as for exploring the genetic diversity within the L. (V.) guyanensis complex.


Assuntos
Leishmania guyanensis , Leishmania , Psychodidae , Animais , Humanos , Leishmania guyanensis/genética , Proteínas de Choque Térmico HSP70/genética , Filogenia , Colômbia/epidemiologia , Teorema de Bayes , Leishmania/genética , Mamíferos
11.
Parasit Vectors ; 15(1): 399, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316748

RESUMO

BACKGROUND: The aims of the present study were to evaluate and compare the efficacy of blood-feeding in phlebotomines through industrially processed membranes from the small intestine of pigs (used for the production of commercial sausages) and the skin of euthanized chicks. METHODS: Laboratory-bred Lutzomyia longipalpis and different field-caught phlebotomine species were subjected to the artificial feeding systems under similar conditions. Paired tests were performed using the control (skin from euthanized chicks) and test membranes (pig small intestine). The feeding rates were compared by paired t-test, and Pearson correlation was used to examine the relationship between the thickness of the membranes and feeding rate. RESULTS: The feeding rate was greater with the test membrane than with the control membrane for L. longipalpis (t-test, t = -3.3860, P = 0.0054) but not for the most frequent field-caught species, Nyssomyia antunesi (t-test, t = 0.7746, P = 0.4535). The average thicknesses of the control and test membranes were 184 ± 83 µm and 34 ± 12 µm, respectively (Mann-Whitney U-test, U = 0.00, Z = 2.8823, P = 0.0039); however, there was no correlation between feeding rate and membrane thickness. A moderate positive correlation was observed between the number of phlebotomines that fed and the total number of phlebotomines in the cage for each type of membrane and for each species. CONCLUSIONS: The test membrane is a viable alternative for the artificial blood-feeding of phlebotomines, and is thus a potential substitute for the skin of animals that are euthanized for this purpose. Feeding rate was independent of membrane thickness.


Assuntos
Substitutos Sanguíneos , Psychodidae , Animais , Suínos , Insetos Vetores , Apoio Nutricional , Brasil
12.
Biomed Res Int ; 2022: 4231978, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312854

RESUMO

Phleboviruses transmitted by sandflies are among emerging public health threats. A novel Phlebovirus named Ntepes virus (NTPV) was recently described and found to infect humans from a wide geographic area in Kenya. However, the entomologic risk factors of this virus such as the potential vectors and the transmission cycles remain poorly defined. This study assessed the ability of the colonized sandfly Phlebotomus duboscqi to transmit NTPV and determined the bloodmeal host sources of field-collected sandflies from the area where NTPV was found in Baringo County, Kenya. Five-day old laboratory-reared P. duboscqi were orally challenged with an infectious dose of NTPV (≈106.0 pfu/ml) and incubated for up to 15 days postinfection. Individual sandflies were dissected into abdomens, legs, and salivary glands and screened for the virus infection by cell culture. Of the 205 virus-exposed sandflies, 19.5% developed non-disseminated infections in the midgut, with no evidence of virus dissemination or transmission in legs and salivary glands, respectively. The midgut infection rates decreased with increasing extrinsic incubation period (Spearman's correlation, ρ = -0.71). Blood-fed specimens analyzed by polymerase chain reaction (PCR) and sequencing of a region of the mitochondrial 12S rRNA, revealed almost exclusive feeding on humans (98%) represented by the sandflies Sergentomyia schwetzi, S. clydei, S. antennata, S. squamipleuris, S. africana, and Phlebotomus martini. One specimen of S. clydei had fed on cattle (2%). These findings suggest P. duboscqi is an incompetent laboratory vector of NTPV. The high human-feeding rate by diverse sandfly species increases the likelihood of human exposure to pathogens associated with these sandflies. Assessment of the susceptibility of Sergentomyia species to NTPV is recommended given their high human-feeding tendency.


Assuntos
Phlebotomus , Phlebovirus , Psychodidae , Humanos , Bovinos , Animais , Phlebovirus/genética , Quênia , Hábitos
13.
PLoS Negl Trop Dis ; 16(10): e0010347, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36264975

RESUMO

Leishmaniasis on the Indian subcontinent is thought to have an anthroponotic transmission cycle. There is no direct evidence that a mammalian host other than humans can be infected with Leishmania donovani and transmit infection to the sand fly vector. The aim of the present study was to evaluate the impact of sand fly feeding on other domestic species and provide clinical evidence regarding possible non-human reservoirs through experimental sand fly feeding on cows, water buffalo goats and rodents. We performed xenodiagnosis using colonized Phlebotomus argentipes sand flies to feed on animals residing in villages with active Leishmania transmission based on current human cases. Xenodiagnoses on mammals within the endemic area were performed and blood-fed flies were analyzed for the presence of Leishmania via qPCR 48hrs after feeding. Blood samples were also collected from these mammals for qPCR and serology. Although we found evidence of Leishmania infection within some domestic mammals, they were not infectious to vector sand flies. Monitoring infection in sand flies and non-human blood meal sources in endemic villages leads to scientific proof of exposure and parasitemia in resident mammals. Lack of infectiousness of these domestic mammals to vector sand flies indicates that they likely play no role, or a very limited role in Leishmania donovani transmission to people in Bihar. Therefore, a surveillance system in the peri-/post-elimination phase of visceral leishmaniasis (VL) must monitor absence of transmission. Continued surveillance of domestic mammals in outbreak villages is necessary to ensure that a non-human reservoir is not established, including domestic mammals not present in this study, specifically dogs.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Leishmaniose , Phlebotomus , Psychodidae , Feminino , Bovinos , Humanos , Cães , Animais , Leishmaniose Visceral/epidemiologia , Gado , Roedores
14.
Parasit Vectors ; 15(1): 377, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261836

RESUMO

BACKGROUND: Leishmania parasites are deposited in the host through sand fly bites along with sand fly saliva. Therefore, salivary proteins are promising vaccine candidates for controlling leishmaniasis. Herein, two immunogenic salivary proteins, PpSP15 from Phlebotomus papatasi and PsSP9 from Phlebotomus sergenti, were selected as vaccine candidates to be delivered by live Leishmania tarentolae as vector. The stepwise in silico protocol advantaged in this study for multi-protein design in L. tarentolae is then described in detail. METHODS: All possible combinations of two salivary proteins, PpSP15 and PsSP9, with or without T2A peptide were designed at the mRNA and protein levels. Then, the best combination for the vaccine candidate was selected based on mRNA and protein stability along with peptide analysis. RESULTS: At the mRNA level, the most favored secondary structure was PpSP15-T2A-PsSP9. At the protein level, the refined three-dimensional models of all combinations were structurally valid; however, local quality estimation showed that the PpSp15-T2A-PsSP9 fusion had higher stability for each amino acid position, with low root-mean-square deviation (RMSD), compared with the original proteins. In silico evaluation confirmed the PpSP15-T2A-PsSP9 combination as a good Th1-polarizing candidate in terms of high IFN-γ production and low IL-10/TGF-ß ratio in response to three consecutive immunizations. Potential protein expression was then confirmed by Western blotting. CONCLUSIONS: The approach presented herein is among the first studies to have privileged protein homology modeling along with mRNA analysis for logical live vaccine design-coding multi-proteins.


Assuntos
Leishmania , Leishmaniose Cutânea , Phlebotomus , Psychodidae , Animais , Phlebotomus/parasitologia , Psychodidae/genética , Interleucina-10 , Leishmaniose Cutânea/parasitologia , Proteínas e Peptídeos Salivares/genética , Leishmania/genética , Vacinas Atenuadas , RNA Mensageiro/genética , Fator de Crescimento Transformador beta , Aminoácidos
15.
Parasit Vectors ; 15(1): 355, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36199150

RESUMO

Phlebotomine sand flies are proven or suspected vectors of several pathogens of importance, including leishmaniasis, bartonellosis and sand fly fevers. Although sand flies have a worldwide distribution, there has been limited research published on sand flies and sand fly-borne pathogens throughout the Greater Mekong Sub-region (GMS). This review followed the PRISMA guidelines to determine the biodiversity and presence of phlebotomine sand flies and their associated pathogens in the GMS, specifically Cambodia, Thailand, the Lao People's Democratic Republic (Laos), Malaysia and Vietnam. A total of 1472 records were identified by searching electronic databases, scanning reference lists of articles and consulting experts in the field. After screening of title and abstracts, 178 records remained and were further screened for original data (n = 34), not having regional data (n = 14), duplication of data (n = 4), records not available (n = 4) and no language translation available (n = 2). A total of 120 studies were then included for full review, with 41 studies on sand fly-related disease in humans, 33 studies on sand fly-related disease in animals and 54 entomological studies focused on sand flies (5 papers contained data on > 1 category), with a majority of the overall data from Thailand. There were relatively few studies on each country, with the exception of Thailand, and the studies applied different methods to investigate sand flies and sand fly-borne diseases, impacting the ability to conduct meaningful meta-analysis. The findings suggest that leishmaniasis in humans and the presence of sand fly vectors have been reported across several GMS countries over the past 100 years, with local transmission in humans confirmed in Thailand and Vietnam. Additionally, local Mundinia species are likely transmitted by biting midges. Findings from this study provide a framework for future investigations to determine the geographic distribution and risk profiles of leishmaniasis and other associated sand fly-borne disease throughout the GMS. It is recommended that researchers expand surveillance efforts across the GMS, with an emphasis placed on entomological surveys, syndromic and asymptomatic monitoring in both humans and animals and molecular characterization of sand flies and sand fly-borne pathogens, particularly in the understudied countries of Cambodia, Vietnam and Laos.


Assuntos
Leishmania , Leishmaniose , Phlebotomus , Psychodidae , Animais , Humanos , Insetos Vetores , Leishmaniose/epidemiologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-36197421

RESUMO

This study was conducted to characterize the transmission cycle of the tegumentary leishmaniasis (TL) in an old colonization area at Pernambuco State, Brazil. The aims were to identify autochthonous cases, sandflies fauna, domestic animals as possible reservoir hosts and the Leishmania species involved in this endemic area. A total of 168 suspected human cases of TL and 272 domestic animals (canine, feline, equine, goat, and sheep) were included. The sandflies were captured and identified by species. Patients were predominantly male and the average age was 37+18.1 years old. Of 85 patients who had skin lesions, 25.6% of them had direct positive smears for TL and 34 isolates were identified as Leishmania (Viannia) braziliensis. The confirmation for TL diagnosed by molecular detection (PCR) was almost three times more sensitive than the direct test [p < 0.001; PR = 2.72] associated with clinical examination. The Kappa test on PCR between two different specimens, biopsy, and skin lesion swab was 60.8% (p < 0.001). More than 200 specimens of sandflies (80 males and 159 females) were captured and identified as Lutzomyia whitmani (99.6%) and Lu. evandroi (0.4%). The detection of L. (V.) braziliensis by Real-Time PCR in the blood of a captured fed female was positive in 59.3% of Lu. whitmani. Of the 272 domestic animals included, 61.76% were male (n = 168). Thirty-six animals (13.2%) had lesions compatible with TL (34 dogs, 1 cat and 1 sheep) and 3 of them, all dogs, had lesions on the snout, showing destruction of cartilage and mucosa. The study suggests the participation of domestic animals as possible reservoirs. However, further studies are necessary to better understand the transmission cycle and take recommended measures in order to control the disease.


Assuntos
Leishmania braziliensis , Leishmania , Leishmaniose Cutânea , Psychodidae , Adolescente , Adulto , Animais , Brasil/epidemiologia , Gatos , Cães , Feminino , Cavalos , Humanos , Leishmania braziliensis/genética , Leishmaniose Cutânea/diagnóstico , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/veterinária , Masculino , Pessoa de Meia-Idade , Ovinos , Adulto Jovem
17.
Viruses ; 14(10)2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36298764

RESUMO

Cases of sand fly-borne diseases in the Emilia-Romagna region, such as meningitis caused by Toscana virus and human leishmaniasis, are reported annually through dedicated surveillance systems. Sand flies are abundant in the hilly part of the region, while the lowland is unsuitable habitat for sand flies, which are found in lower numbers in this environment with respect to the hilly areas. In this study, we retrieved sand flies collected during entomological surveillance of the West Nile virus (from 2018 to 2021) to assess their abundance and screen them for the presence of pathogens. Over the four-year period, we collected 3022 sand flies, more than half in 2021. The most abundant sand fly species was Phlebotomus (Ph.) perfiliewi, followed by Ph. perniciosus; while more rarely sampled species were Ph. papatasi, Ph. mascittii and Sergentomyia minuta. Sand flies were collected from the end of May to the end of September. The pattern of distribution of the species is characterized by an abundant number of Ph. perfiliewi in the eastern part of the region, which then falls to almost none in the western part of the region, while Ph. perniciosus seems more uniformly distributed throughout. We tested more than 1500 female sand flies in 54 pools to detect phleboviruses and Leishmania species using different PCR protocols. Toscana virus and Leishmania infantum, both human pathogens, were detected in 5 pools and 7 pools, respectively. We also detected Fermo virus, a phlebovirus uncharacterized in terms of relevance to public health, in 4 pools. We recorded different sand fly abundance in different seasons in Emilia-Romagna. During the season more favorable for sand flies, we also detected pathogens transmitted by these insects. This finding implies a health risk linked to sand fly-borne pathogens in the surveyed area in lowland, despite being considered a less suitable habitat for sand flies with respect to the hilly areas.


Assuntos
Leishmania infantum , Phlebotomus , Phlebovirus , Psychodidae , Vírus da Febre do Flebótomo Napolitano , Animais , Feminino , Humanos , Phlebovirus/genética , Itália
18.
ScientificWorldJournal ; 2022: 9382154, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36132438

RESUMO

An entomological survey was carried out in the locality of Aichoune to conduct a study on sand flies, species composition, and monthly relative abundance. This study is essential for the implementation of integrated vector management control. Insects collection was carried out twice a month from January 2013 to December 2014 by means of adhesive and CDC-type light traps. A total of 5441 sand flies were collected with the predominance of males (a sex ratio = 1.89). The sampled specimens consist of seven species divided into two genera: Phlebotomus (99.55%) and Sergentomyia (0.44%). Phlebotomus sergenti was the dominant species with an average annual proportion of 47.38%, followed by P. perniciosus (37.32%), P. longicuspis (8,56%), P. papatasi (6.23%), and P. ariasi (0.05%). The genus Sergentomyia was less common (0.44%). S.minuta was represented only by 0.36% and S. fallax by 0.07%. The species dynamics showed a unimodal evolution for P. sergenti and P. papatasi. They were active from May to October. P. perniciosus presents a trimodal trend showing the most relevant peak in August. The highest number of specimens was collected in June, when the temperature reaches an annual average value of 25.5°C. The obtained results will help us better understand the leishmaniasis transmission dynamics in the Aichoune locality and will contribute to the design of a surveillance strategy.


Assuntos
Leishmaniose Cutânea , Phlebotomus , Psychodidae , Animais , Feminino , Leishmaniose Cutânea/epidemiologia , Masculino , Marrocos/epidemiologia , Temperatura
19.
Parasitol Res ; 121(11): 3331-3336, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36076092

RESUMO

To date, sand flies (Phlebotominae) are the only recognized biological vectors of Leishmania infantum, the causative agent of human visceral leishmaniasis, which is endemic in the Mediterranean basin and also widespread in Central and South America, the Middle East, and Central Asia. Dogs are the main domestic reservoir of zoonotic visceral leishmaniasis, and the role of secondary vectors such as ticks and fleas and particularly Rhipicephalus sanguineus (the brown dog tick) in transmitting L. infantum has been investigated. In the present paper, the presence of Leishmania DNA was investigated in questing Ixodes ricinus ticks collected from 4 rural areas included in three parks of the Emilia-Romagna Region (north-eastern Italy), where active foci of human visceral leishmaniasis have been identified. The analyses were performed on 236 DNA extracts from 7 females, 6 males, 72 nymph pools, and 151 larvae pools. Four samples (1.7%) (i.e., one larva pool, 2 nymph pools, and one adult male) tested positive for Leishmania kDNA. To the best of our knowledge, this is the first report of the presence of Leishmania kDNA in questing I. ricinus ticks collected from a rural environment. This finding in unfed larvae, nymphs, and adult male ticks supports the hypothesis that L. infantum can have both transstadial and transovarial passage in I. ricinus ticks. The potential role of I. ricinus ticks in the sylvatic cycle of leishmaniasis should be further investigated.


Assuntos
Ixodes , Ixodidae , Leishmania infantum , Leishmaniose Visceral , Psychodidae , Rhipicephalus sanguineus , Animais , DNA de Cinetoplasto , Cães , Feminino , Humanos , Ixodes/genética , Ixodidae/genética , Leishmania infantum/genética , Leishmaniose Visceral/veterinária , Masculino , Ninfa , Psychodidae/genética , Rhipicephalus sanguineus/genética
20.
ScientificWorldJournal ; 2022: 4095129, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36118290

RESUMO

The infections transmitted by sand flies (Diptera, Psychodidae) pose always a real health problem due to the increasing number of cases detected each year and the annual emergence of new leishmaniasis outbreaks. This study evaluated the temporal evolution of six species of sand flies in five stations inventoried between May 2017 and April 2018, in order to determine for the first time the extent of cutaneous leishmaniasis (CL) transmission in the city of Fez. The monthly impact of Fez sand fly density has been studied using all multivariate statistical analyses, including multiple factor correspondence analysis (MCA), which were performed using XLSTAT and the version of SPSS 20.0 test. Differences between concentrations were considered significant if P < 0.05. To better study the results obtained, different ecological indices have been studied. This study showed that these vectors developed in different sectors of the city of Fez. A total of 816 sand flies were collected from five stations in the city, belonging to three species of the genus Phlebotomus (46.82%) and three species of the genus Sergentomyia (53.18%). The seasonal fluctuation of the average density followed a bimodal evolution for the three stations Dhar Richa, Ain Nokbi, and Boujloud. The stations of Ain Nokbi (0.87 ph/m2) and Dhar Richa (0.467 ph/m2) exposed the sites to a high average density with a maximum peak during August (1.965 ph/m2) and July (1.87 Ph/m2), respectively. S. minuta (44.24%), Ph. sergenti (26.96%), Ph. perniciosus (10.78%), and Ph. papatasi (9.07%) were the most qualified species. The calculated P value is above the 5% significance level, so the relative abundance of these species between study sites shows no significant difference. The period of phlebotomy activity of the genus Phlebotomus in Fez lasts seven months from May to November with a bimodal or trimodal evolution and varies according to the species or the surveyed station. The seasonal fluctuation of sand flies could be conditioned by climatic factors where the period of activity of the species coincides with the hot months (May, June, July, and August). We have observed that the temperature factor favors the prevalence of sand flies, while the difference in the relative abundance of species between the sites is related to the difference in the bioecological conditions of each site.


Assuntos
Leishmaniose Cutânea , Psychodidae , Animais , Insetos Vetores , Leishmaniose Cutânea/epidemiologia , Marrocos/epidemiologia , Estações do Ano
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