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Biological Procedures Online Nov 2023Arthropods transmit a wide range of pathogens of importance for the global health of humans, animals, and plants. One group of these arthropod vectors, Culicoides biting...
BACKGROUND
Arthropods transmit a wide range of pathogens of importance for the global health of humans, animals, and plants. One group of these arthropod vectors, Culicoides biting midges (Diptera: Ceratopogonidae), is the biological vector of several human and animal pathogens, including economically important livestock viruses like bluetongue virus (BTV). Like other arthropod-borne viruses (arboviruses), Culicoides-borne viruses must reach and replicate in the salivary apparatus, from where they can be transmitted to susceptible hosts through the saliva during subsequent blood feeding. Despite the importance of the salivary gland apparatus for pathogen transmission to susceptible animals from the bite of infected Culicoides, these structures have received relatively little attention, perhaps due to the small size and fragility of these vectors.
RESULTS
In this study, we developed techniques to visualize the infection of the salivary glands and other soft tissues with BTV, in some of the smallest known arbovirus vectors, Culicoides biting midges, using three-dimensional immunofluorescence confocal microscopy. We showed BTV infection of specific structures of the salivary gland apparatus of female Culicoides vectors following oral virus uptake, related visualisation of viral infection in the salivary apparatus to high viral RNA copies in the body, and demonstrated for the first time, that the accessory glands are a primary site for BTV replication within the salivary apparatus.
CONCLUSIONS
Our work has revealed a novel site of virus-vector interactions, and a novel role of the accessory glands of Culicoides in arbovirus amplification and transmission. Our approach would also be applicable to a wide range of arbovirus vector groups including sand flies (Diptera: Psychodidae), as well as provide a powerful tool to investigate arbovirus infection and dissemination, particularly where there are practical challenges in the visualization of small size and delicate tissues of arthropods.
PubMed: 37932658
DOI: 10.1186/s12575-023-00221-2 -
Viruses Oct 2023Fermo virus is a that is increasingly reported in sand flies from northern Italy. The natural cycle is not fully understood, but the virus has been detected by direct...
Fermo virus is a that is increasingly reported in sand flies from northern Italy. The natural cycle is not fully understood, but the virus has been detected by direct methods only in sand flies. Although there is serological evidence that it can infect vertebrates, the virus has not been directly detected in animals or humans. Here, we have developed and reported a specific real-time PCR for Fermo virus. The availability of the described method will be useful to characterize the epidemiology of the FERV, ensuring, compared to previously available protocols, a more sensitive detection in insects and the possible detection in vertebrates to evaluate the presence of reservoirs and the pathogenic potential of the virus in humans or animals.
Topics: Animals; Humans; Phlebovirus; Real-Time Polymerase Chain Reaction; Psychodidae; Italy
PubMed: 37896859
DOI: 10.3390/v15102082 -
Pathogens (Basel, Switzerland) Sep 2023Phlebotomine sand flies (Diptera: Psychodidae) are the principal vectors of phleboviruses and spp., the causative agents of leishmaniases. The Mediterranean sand fly...
Phlebotomine sand flies (Diptera: Psychodidae) are the principal vectors of phleboviruses and spp., the causative agents of leishmaniases. The Mediterranean sand fly fauna is diverse, and leishmaniasis, mainly caused by is endemic in the Balkan countries. Despite recent entomological surveys, only some districts of Kosovo have been sampled for sand flies, with no proof/confirmation of . This study aimed to gain further insights into the species composition of natural sand fly populations in previously unsampled districts and areas in Kosovo without reports of leishmaniasis and to detect DNA in sand flies. A sand fly survey was conducted in 2022 in all seven districts of Kosovo. Collected females were screened for DNA by PCR. Positive samples were sequenced and subjected to maximum likelihood analysis with reference sequences for further molecular characterization. The trapping activities at 114 different localities resulted in 3272 caught specimens, comprising seven sand fly species of two genera, namely , , , , , and . DNA was detected in three individual sand flies of and This study provides the most extensive sand fly survey in Kosovo and reports the first record of DNA in sand flies, indicating autochthonous circulation of .
PubMed: 37887706
DOI: 10.3390/pathogens12101190 -
Journal of Vector Borne Diseases 2023Present study was conducted to carry out morphological and molecular confirmation of sandflies collected at the Department of Parasitology, Faculty of Veterinary and...
Present study was conducted to carry out morphological and molecular confirmation of sandflies collected at the Department of Parasitology, Faculty of Veterinary and Animal Sciences, R.S. Pura, Jammu, India. Larva was maggot like with large head, thorax and abdomen with typical black head, 12 abdominal segments and last abdominal segment carried two pairs of caudal bristles with matchstick hairs on each segment. The adult fly possessed head, abdomen and thorax. Head consisted of pair of long, hairy and beaded antenna, proboscis and one pair of prominent black eyes. Thorax possessed a pair of wings and three pairs of legs, wings were hairy and pointed with 2 longitudinal vein branched twice. The abdominal segments were covered with small hairs and last abdominal segment was having a pair of anal recti. These identification characteristics confirmed the fly under study as Phlebotomus argentipes that confirms its occurance in this region. Molecular characterization of identified flies was carried out on positive morophological flies. Confirmation of Phlebotomus species was ascertained by amplifying the 18S ribosomal RNA gene sequence using PCR. Clear amplification was observed for Phlebotomus argentipes (538 bp). After sequencing/genotyping, Phlebotomus argentipes (OP646634) isolate of present study was clustering in same clade with Phlebotomus argentipes sequences obtained from GeneBank from other locations across globe, irrespective of their geographical location, thus providing the molecular evidence of this species present in Jammu region of North India.
Topics: Animals; Phlebotomus; Psychodidae; Insect Vectors; Leishmaniasis; India
PubMed: 37843245
DOI: 10.4103/0972-9062.374037 -
Revista Da Sociedade Brasileira de... 2023Here, Leishmania presence in sand flies from Três Lagoas, Mato Grosso do Sul, Brazil, after visceral leishmaniasis (VL) was investigated.
Natural infection of Lutzomyia longipalpis (Lutz & Neiva, 1912) by Leishmania infantum in a municipality with a high incidence of visceral leishmaniasis in the Brazilian Midwest.
BACKGROUND
Here, Leishmania presence in sand flies from Três Lagoas, Mato Grosso do Sul, Brazil, after visceral leishmaniasis (VL) was investigated.
METHODS
In April 2022, two light traps were deployed within and around the residence for two days post-VL case report.
RESULTS
A total of 120 Lutzomyia longipalpis were collected. Suprapyloric flagellates were found in a female sand fly with eggs and residual blood during midgut dissection. Sequencing of ITS1 and cytb fragments confirmed Leishmania infantum DNA and identified Homo sapiens as the blood source, respectively.
CONCLUSIONS
This study emphasizes the importance of monitoring sand flies in VL endemic areas.
Topics: Animals; Female; Leishmaniasis, Visceral; Leishmania infantum; Brazil; Incidence; Insect Vectors; Psychodidae
PubMed: 37792832
DOI: 10.1590/0037-8682-0259-2023 -
Biodiversity Data Journal 2023Prior to this study, the moth flies in The Netherlands were represented by 61 species. Our findings derive from a citizen-science expedition in the Vondelpark in...
BACKGROUND
Prior to this study, the moth flies in The Netherlands were represented by 61 species. Our findings derive from a citizen-science expedition in the Vondelpark in Amsterdam, one of the oldest public parks and best known parks in The Netherlands. The combination of citizen science and the exploration of a well-known urban park has allowed us to contribute to the knowledge of moth fly species present in The Netherlands. The findings from this study provide valuable insights into the distribution, taxonomy and genetic resources of and species, enhancing our understanding of insect biodiversity and promoting future research in this field.
NEW INFORMATION
Our study provides two new geographical records of the moth flies in The Netherlands, namely, Haseman, 1907 and (Tonnoir, 1920) elevating the total number of species to 63. Furthermore, we provide re-descriptions of the females of (Eaton, 1893) and (Tonnoir, 1919). Additionally, we make available for the first time, the sequence of the 5'-end of the cytochrome c oxidase subunit I () gene or Barcodes for , and . These Barcodes serve as valuable tools for future species identification within the genus.
PubMed: 37767004
DOI: 10.3897/BDJ.11.e108636 -
PLoS Neglected Tropical Diseases Sep 2023In South-East Asia, Thailand is the country with the highest number of human autochthonous cases of leishmaniases mostly due to Leishmania martiniquensis. Their...
Phlebotomine sand flies (Diptera, Psychodidae) from Pha Tong cave, Northern Thailand with a description of two new species and taxonomical thoughts about Phlebotomus stantoni.
BACKGROUND
In South-East Asia, Thailand is the country with the highest number of human autochthonous cases of leishmaniases mostly due to Leishmania martiniquensis. Their transmission remains unresolved to date even though sand flies are known vectors of leishmaniases. As such, we focused a study on the sand fly fauna of a cave in Thailand to explore the biodiversity of potential Leishmania vectors.
MAIN RESULTS
We carried out an inventory in Pha Tong cave. We caught and identified 570 Phlebotomine sand flies (452 females and 118 males) and identified 14 species belonging to the genera Phlebotomus, Idiophlebotomus, Chinius, Sergentomyia and Grassomyia. Among these 14 species, two could not be related to known sand fly species. Herein, we propose the description of two new sand fly species, previously unknown to science. The first new species, Phlebotomus shadenae n. sp. is a sand fly of the subgenus Anaphlebotomus. It is morphologically close to Ph. stantoni, a species widely distributed throughout Southeast Asia. However, it differs by the length of the genital filaments in males or by the length of the ducts of the spermathecae in females as well as the high divergence of cytochrome b sequences. Additionally, we revised the systematics of the subgenus Anaphlebotomus and reinstated, by examination of its holotype, the validity of Ph. maynei, an Indian wrongly considered as a synonym of Ph. stantoni in the past. The second new species, Sergentomyia maiae n. sp., differs from a species in the same group, Se. barraudi, by an original cibarial double row of vertical teeth as well as by molecular data.
CONCLUSIONS
We propose the description of two new sand fly species for Science with morphological and molecular evidence. Ph. shadenae n. sp. was also found to be distributed in the south of Thailand and in Laos. Future studies need to determine whether these two species can play a role as vectors of Leishmania parasites, Trypanosomatids or Phlebovirus. Most of the species caught in the present study are strictly cavernicolous except Grassomyia sp. and a few Sergentomyia.
PubMed: 37729218
DOI: 10.1371/journal.pntd.0011565 -
The American Journal of Tropical... Nov 2023The success of the visceral leishmaniasis (VL) elimination program largely depends on cost-effective vector control measures. Our goal was to investigate the longevity...
The success of the visceral leishmaniasis (VL) elimination program largely depends on cost-effective vector control measures. Our goal was to investigate the longevity of the efficacy of insecticidal wall painting (IWP), a new vector control tool, compared with a routine indoor residual spraying (IRS) program for reducing the VL vector density in Bangladesh. This study is the extension of our recent IWP study for VL vector management in Bangladesh, which was undertaken in seven highly VL endemic villages of the Mymensingh district with a 12-month follow-up. In this 24-months follow-up study, we collected sand flies additionally at 15, 18, 21, and 24 months since the interventions from the IWP and control (where the program did routine IRS) clusters to examine the longevity of the efficacy of IWP on sand fly density reduction and mortality. The difference-in-differences regression models were used to estimate the effect of IWP on sand fly reduction against Program IRS. The IWP showed excellent performance in reducing sand fly density and increasing sand fly mortality compared with Program IRS. The effect of IWP for controlling sand flies was statistically significant for up to at least 24 months. The mean female Phlebotomus argentipes density reduction ranged from -56% to -83%, and the P. argentipes sand fly mortality ranged from 81% to 99.5% during the 24-month follow-up period. Considering the duration of the efficacy of IWP for controlling VL vectors, Bangladesh National Kala-azar Elimination Program may consider IWP as the best alternative to IRS for the subsequent phases of the program.
Topics: Animals; Female; Insecticides; Leishmaniasis, Visceral; Insect Control; Bangladesh; Follow-Up Studies; Insect Vectors; Phlebotomus; Psychodidae; India
PubMed: 37722667
DOI: 10.4269/ajtmh.22-0809 -
Frontiers in Cellular and Infection... 2023Female sand flies are hematophagous, feeding on animals and in the process serve as vectors for , the parasites that cause leishmaniasis in humans. Leishmaniasis are a...
INTRODUCTION
Female sand flies are hematophagous, feeding on animals and in the process serve as vectors for , the parasites that cause leishmaniasis in humans. Leishmaniasis are a group of parasitic neglected tropical diseases in 98 countries including Nigeria and kills ~60,000 people/year. In Nigeria, Sokoto State is endemic to leishmaniasis but there is a knowledge gap on the identity of the prevalent sand flies and the species they transmit. Hence, this cross-sectional study was designed to take inventory of the species of sand flies in Sokoto using genetic methods.
METHODS
1,260 (310 females) sand flies were collected from three Local Government Areas (L.G.A) of Sokoto State- Wamakko, Sokoto South and Kware. Genomic DNA was extracted from each fly and DNA amplification by polymerase chain reaction (PCR) was carried out on the DNA samples using primers targeting the arthropods mitochondrial cytochrome oxidase subunit 1 () gene, and nested PCR with primers targeting the gene for internal transcribed spacer-1 () of ribosomal RNA . The PCR products were sequenced.
RESULTS
Gene sequence analysis revealed five species of sand flies belonging to the old-world genera namely and . The identified species were (6.45%), (6.45%), (9.7%), (9.7%), (67.7%). Within the sampling period, sand flies were most abundant in the rainy months of August (104/33.5%) and September (116/37.4%) with all the five identified species occurring. Sequence analysis of gene identified in two sand flies (2/310)- (from Sokoto South) and (from Wamakko). BLAST search in NCBI and phylogenetic analysis revealed that the sand fly species are related to the species reported in different parts of Africa, while the is identical to strain reported in Brazil (KY379083.1).
DISCUSSION
and four species belonging to the genus are the most prevalent sand flies in Sokoto State, Nigeria and they harbor solely. The results shed light on why visceral leishmaniasis is the most predominant form of the disease. Therefore, we recommend that adequate care for dogs must be instituted as dogs are the major animal reservoir for .
Topics: Humans; Female; Animals; Dogs; Psychodidae; Nigeria; Cross-Sectional Studies; Phylogeny; Phlebotomus; Leishmania infantum
PubMed: 37719668
DOI: 10.3389/fcimb.2023.1219629 -
Revista Brasileira de Parasitologia... 2023In 2017, the Brazilian State of Amapá registered the first occurrence of visceral leishmaniosis (VL) in 17 dogs in the outskirts of the capital, Macapá. Given the lack...
In 2017, the Brazilian State of Amapá registered the first occurrence of visceral leishmaniosis (VL) in 17 dogs in the outskirts of the capital, Macapá. Given the lack of knowledge on phlebotomines in that area, this study aimed to survey the fauna of these Diptera. Sampling was performed using CDC light traps placed at ten sampling sites. The specimens captured were Evandromyia walkeri (n=237), Nyssomyia antunesi (n=65) and Bichromomyia flaviscutellata (n=6). The phlebotomine species composition resulted in low species diversity, and none of the main vectors of the etiological agent of VL were identified in the study area.
Topics: Dogs; Animals; Psychodidae; Leishmania infantum; Brazil; Leishmaniasis, Visceral; Dog Diseases
PubMed: 37703122
DOI: 10.1590/S1984-29612023054