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PLoS Neglected Tropical Diseases Jul 2017Leishmaniases are parasitic diseases present worldwide that are transmitted to the vertebrate host by the bite of an infected sand fly during a blood feeding.... (Review)
Review
BACKGROUND
Leishmaniases are parasitic diseases present worldwide that are transmitted to the vertebrate host by the bite of an infected sand fly during a blood feeding. Phlebotomine sand flies inoculate into the mammalian host Leishmania parasites embedded in promastigote secretory gel (PSG) with saliva, which is composed of a diverse group of molecules with pharmacological and immunomodulatory properties.
METHODS AND FINDINGS
In this review, we focus on 3 main aspects of sand fly salivary molecules: (1) structure and composition of salivary glands, including the properties of salivary molecules related to hemostasis and blood feeding, (2) immunomodulatory properties of salivary molecules and the diverse impacts of these molecules on leishmaniasis, ranging from disease exacerbation to vaccine development, and (3) use of salivary molecules for field applications, including monitoring host exposure to sand flies and the risk of Leishmania transmission. Studies showed interesting differences between salivary proteins of Phlebotomus and Lutzomyia species, however, no data were ever published on salivary proteins of Sergentomyia species.
CONCLUSIONS
In the last 15 years, numerous studies have characterized sand fly salivary proteins and, in parallel, have addressed the impact of such molecules on the biology of the host-sand fly-parasite interaction. The results obtained shall pave the way for the development of field-application tools that could contribute to the management of leishmaniasis in endemic areas.
Topics: Animals; Feeding Behavior; Leishmania; Psychodidae; Saliva; Salivary Proteins and Peptides
PubMed: 28704370
DOI: 10.1371/journal.pntd.0005600 -
Memorias Do Instituto Oswaldo Cruz 2020In Acre state, Brazil, the dissemination of cutaneous leishmaniasis has increased in recent years, with limited knowledge of the potential Leishmania spp. vectors... (Review)
Review
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.
Topics: Animals; Brazil; DNA; DNA, Protozoan; Female; Insect Vectors; Leishmania; Leishmaniasis, Cutaneous; Polymerase Chain Reaction; Psychodidae
PubMed: 33206821
DOI: 10.1590/0074-02760200157 -
Parasites & Vectors May 2014We review existing information on the epidemiology of American Cutaneous Leishmaniasis (ACL) in Panama, with emphasis on the bionomics of anthropophilic Lutzomyia sand... (Review)
Review
We review existing information on the epidemiology of American Cutaneous Leishmaniasis (ACL) in Panama, with emphasis on the bionomics of anthropophilic Lutzomyia sand fly species. Evidence from Panamanian studies suggests that there are six anthropophilic species in the country: Lutzomyia trapidoi, Lu. panamensis, Lu. gomezi, Lu. ylephiletor, Lu. sanguinaria and Lu. pessoana (Henceforth Lu. carrerai thula). In general, these taxa are abundant, widespread and feed opportunistically on their hosts, which make them potential transmitters of pathogens to a broad range of wildlife, domesticated animals and humans. Furthermore, nearly all man-biting species in Panama (with the exception of Lu. gomezi) expand demographically during the rainy season when transmission is likely higher due to elevated Leishmania infection rates in vector populations. Despite this, data on the distribution and prevalence of ACL suggest little influence of vector density on transmission intensity. Apart from Lu. trapidoi, anthropophilic species seem to be most active in the understory, but vertical stratification, as well as their opportunistic feeding behavior, could vary geographically. This in turn seems related to variation in host species composition and relative abundance across sites that have experienced different degrees of human alteration (e.g., deforestation) in leishmaniasis endemic regions of Panama.
Topics: Animals; History, 20th Century; History, 21st Century; Humans; Leishmaniasis, Cutaneous; Panama; Psychodidae
PubMed: 24886629
DOI: 10.1186/1756-3305-7-218 -
Acta Tropica Feb 2023The accurate identification of sandfly species is crucial because some species transmit medically significant diseases, including leishmaniasis, bartonellosis and...
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.
Topics: Animals; China; Cytochromes b; DNA Barcoding, Taxonomic; DNA, Mitochondrial; DNA, Ribosomal; Phlebotomus; Phylogeny; Psychodidae
PubMed: 36529191
DOI: 10.1016/j.actatropica.2022.106798 -
Parasites & Vectors Apr 2015To investigate the transmission of phleboviruses, a total of 7,057 sandflies were collected in well-known foci of cutaneous leishmaniasis and were identified to species...
To investigate the transmission of phleboviruses, a total of 7,057 sandflies were collected in well-known foci of cutaneous leishmaniasis and were identified to species level according to morphological characters.Collected sandflies were tested by Nested PCR for the presence of Phleboviruses and subsequently by viral isolation on Vero cells. The corresponding products were sequenced. Toscana virus was isolated, for the first time, from 5 pools of sandflies.Hence, Toscana virus should be considered a potential risk that threatens public health and clinicians should be aware of the role of Toscana virus in cases of meningitis and encephalitis in Morocco.
Topics: Animals; Insect Vectors; Morocco; Polymerase Chain Reaction; Psychodidae; Sandfly fever Naples virus; Virus Cultivation
PubMed: 25886511
DOI: 10.1186/s13071-015-0826-1 -
PLoS Neglected Tropical Diseases Jul 2018The Lutzomyia longipalpis complex has a wide but discontinuous distribution in Latin America, extending throughout the Neotropical realm between Mexico and northern...
BACKGROUND
The Lutzomyia longipalpis complex has a wide but discontinuous distribution in Latin America, extending throughout the Neotropical realm between Mexico and northern Argentina and Uruguay. In the Americas, this sandfly is the main vector of Leishmania infantum, the parasite responsible for Visceral Leishmaniasis (VL). The Lu. longipalpis complex consists of at least four sibling species, however, there is no current consensus on the number of haplogroups, or on their divergence. Particularly in Argentina, there have been few genetic analyses of Lu. longipalpis, despite its southern expansion and recent colonization of urban environments. The aim of this study was to analyze the genetic diversity and structure of Lu. longipalpis from Argentina, and to integrate these data to re-evaluate the phylogeography of the Lu. longipalpis complex using mitochondrial markers at a Latin American scale.
METHODOLOGY/PRINCIPAL FINDINGS
Genetic diversity was estimated from six sites in Argentina, using a fragment of the ND4 and the 3´ extreme of the cyt b genes. Greatest genetic diversity was found in Tartagal, Santo Tomé and San Ignacio. There was high genetic differentiation of Lu. longipalpis in Argentina using both markers: ND4 (FST = 0.452, p < 0.0001), cyt b (FST = 0.201, p < 0.0001). Genetic and spatial Geneland analyses reveal the existence of two primary genetic clusters in Argentina, cluster 1: Tartagal, Santo Tomé, and San Ignacio; cluster 2: Puerto Iguazú, Clorinda, and Corrientes city. Phylogeographic analyses using ND4 and cyt b gene sequences available in GenBank from diverse geographic sites suggest greater divergence than previously reported. At least eight haplogroups (three of these identified in Argentina), each separated by multiple mutational steps using the ND4, are differentiated across the Neotropical realm. The divergence of the Lu. longipalpis complex from its most recent common ancestor (MRCA) was estimated to have occurred 0.70 MYA (95% HPD interval = 0.48-0.99 MYA).
CONCLUSIONS/SIGNIFICANCE
This study provides new evidence supporting two Lu. longipalpis genetic clusters and three of the total eight haplogroups circulating in Argentina. There was a high level of phylogeographic divergence among the eight haplogroups of the Lu. longipalpis complex across the Neotropical realm. These findings suggest the need to analyze vector competence, among other parameters intrinsic to a zoonosis, according to vector haplogroup, and to consider these in the design and surveillance of vector and transmission control strategies.
Topics: Animals; Argentina; Cytochromes b; Female; Genetic Variation; Insect Proteins; Insect Vectors; Male; Phylogeny; Phylogeography; Psychodidae; Uruguay
PubMed: 29975695
DOI: 10.1371/journal.pntd.0006614 -
Parasites & Vectors Jan 2021Phlebotomines are a group of insects which include vectors of the Leishmania parasites that cause visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL), diseases...
BACKGROUND
Phlebotomines are a group of insects which include vectors of the Leishmania parasites that cause visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL), diseases primarily affecting populations of low socioeconomic status. VL in Brazil is caused by Leishmania infantum, with transmission mainly attributed to Lutzomyia longipalpis, a species complex of sand fly, and is concentrated mainly in the northeastern part of the country. CL is distributed worldwide and occurs in five regions of Brazil, at a higher incidence in the north and northeast regions, with etiological agents, vectors, reservoirs and epidemiological patterns that differ from VL. The aim of this study was to determine the composition, distribution and ecological relationships of phlebotomine species in an Atlantic Forest conservation unit and nearby residential area in northeastern Brazil.
METHODS
Centers for Disease Control and Shannon traps were used for collections, the former at six points inside the forest and in the peridomestic environment of surrounding residences, three times per month for 36 months, and the latter in a forest area, once a month for 3 months. The phlebotomines identified were compared with climate data using simple linear correlation, Pearson's correlation coefficient and cross-correlation. The estimate of ecological parameters was calculated according to the Shannon-Wiener diversity index, standardized index of species abundance and the dominance index.
RESULTS
A total of 75,499 phlebotomines belonging to 11 species were captured in the CDC traps, the most abundant being Evandromyia walkeri, Psychodopygus wellcomei and Lu. longipalpis. Evandromyia walkeri abundance was most influenced by temperature at collection time and during the months preceding collection and rainfall during the months preceding collection. Psychodopygus wellcomei abundance was most affected by rainfall and relative humidity during the collection month and the month immediately preceding collection time. Lutzomyia longipalpis abundance showed a correlation with temperature and the rainfall during the months preceding collection time. The Shannon trap contained a total of 3914 phlebotomines from these different species. Psychodopygus wellcomei, accounting for 91.93% of the total, was anthropophilic and active mainly at night.
CONCLUSIONS
Most of the species collected in the traps were seasonal and exhibited changes in their composition and population dynamics associated with local adaptions. The presence of vectors Ps. wellcomei and Lu. longipalpis underscore the epidemiological importance of these phlebotomines in the conservation unit and surrounding anthropized areas. Neighboring residential areas should be permanently monitored to prevent VL or CL transmission and outbreaks.
Topics: Animals; Brazil; Conservation of Natural Resources; Female; Forests; Insect Vectors; Leishmania infantum; Leishmaniasis, Cutaneous; Male; Population Dynamics; Psychodidae; Seasons; Temperature
PubMed: 33430944
DOI: 10.1186/s13071-020-04523-2 -
Memorias Do Instituto Oswaldo Cruz Jul 2017The sandfly Trichophoromyia auraensis has recently evolved as a proven vector of Leishmania (Viannia) endemic to state of Acre in the north of Brazil. This note is...
The sandfly Trichophoromyia auraensis has recently evolved as a proven vector of Leishmania (Viannia) endemic to state of Acre in the north of Brazil. This note is intended to propose a correction in the report of the first occurrence of natural infection of Leishmania (Viannia) in this species. We and the other scientific groups reinforced that Tr. auraensis is a possible vector involved in the transmission of American cutaneous leishmaniasis in Acre, Brazil.
Topics: Animals; Brazil; Insect Vectors; Leishmania; Leishmaniasis, Cutaneous; Psychodidae
PubMed: 28591315
DOI: 10.1590/0074-02760170024 -
Parasite (Paris, France) 2017Laboratory colonies of phlebotomine sand flies are necessary for experimental study of their biology, behaviour and mutual relations with disease agents and for testing...
Laboratory colonies of phlebotomine sand flies are necessary for experimental study of their biology, behaviour and mutual relations with disease agents and for testing new methods of vector control. They are indispensable in genetic studies and controlled observations on the physiology and behaviour of sand flies, neglected subjects of high priority. Colonies are of particular value for screening insecticides. Colonized sand flies are used as live vector models in a diverse array of research projects, including xenodiagnosis, that are directed toward control of leishmaniasis and other sand fly-associated diseases. Historically, labour-intensive maintenance and low productivity have limited their usefulness for research, especially for species that do not adapt well to laboratory conditions. However, with growing interest in leishmaniasis research, rearing techniques have been developed and refined, and sand fly colonies have become more common, enabling many significant breakthroughs. Today, there are at least 90 colonies representing 21 distinct phlebotomine sand fly species in 35 laboratories in 18 countries worldwide. The materials and methods used by various sand fly workers differ, dictated by the availability of resources, cost or manpower constraints rather than choice. This paper is not intended as a comprehensive review but rather a discussion of methods and techniques most commonly used by researchers to initiate, establish and maintain sand fly colonies, with emphasis on the methods proven to be most effective for the species the authors have colonized. Topics discussed include collecting sand flies for colony stock, colony initiation, maintenance and mass-rearing procedures, and control of sand fly pathogens in colonies.
Topics: Animals; Chickens; Cricetinae; Female; Guinea Pigs; Housing, Animal; India; Insect Vectors; Male; Mice; Oviposition; Psychodidae; Rabbits; Transportation
PubMed: 29139377
DOI: 10.1051/parasite/2017041 -
Memorias Do Instituto Oswaldo Cruz 1993The status of phlebotomine sand flies in relationship to the family Psychodidae (Diptera) is reviewed. It is concluded that sand flies should be given familial... (Review)
Review
The status of phlebotomine sand flies in relationship to the family Psychodidae (Diptera) is reviewed. It is concluded that sand flies should be given familial recognition as Phlebotomidae, divided into the subfamilies Phlebotominae and Bruchomyiinae. A comparison is made between the evolution of Psychodidae and Phlebotomidae, and it is concluded that the two families represent contrasting evolutionary experiments at an early stage of the diversification of Diptera.
Topics: Animals; Psychodidae; Terminology as Topic
PubMed: 8107579
DOI: 10.1590/s0074-02761993000200001