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BioMed Research International 2023parasites, which are spread by infected female sand flies, are the cause of the disease leishmaniasis. Although cutaneous leishmaniasis has been found to occur in the...
parasites, which are spread by infected female sand flies, are the cause of the disease leishmaniasis. Although cutaneous leishmaniasis has been found to occur in the Volta Region, there is limited data on vector species and reservoirs. This study focused on the Tsatee community, in the South Dayi District of the Volta Region, and is aimed at identifying the sand fly fauna and detecting the presence of DNA by the use of primers that target the conserved region of spp. minicircle DNA of the parasite kinetoplast. The miniature light traps and hand aspirators provided by the Centers for Disease Control and Prevention (CDC) were used to collect outdoor and indoor sand flies for five months in a guinea woodland and semideciduous forest area. From the collections, 4,580 phlebotomine sand flies were obtained and identified, and females were examined for DNA using PCR. The male flies were 1,202 (26.24%), non-blood-fed females were 3,321 (72.51%), and 57 (1.25%) were blood-fed females. It was observed that species constituted 99.91% of the total collected sand flies with (76.77%) as the predominant species. (0.09%) was the only species identified from the study area. From 283 non-blood-fed sand fly pools and 57 individual blood-fed species screened, DNA was detected in 12 (4.24%) pools and 8 (14.04%) individuals, respectively. It was observed that DNA was detected in all the sand fly species identified except . This study reports the first detection of DNA in in Ghana, with an infection rate of 33.33% (95% CI, 1.23-88.32). The findings suggest that the role of in disease transmission in the study area cannot be discounted. Future studies should include continuous surveillance, blood meal preferences, and vector competence of the various infected phlebotomine sand flies to create effective control measures.
Topics: Humans; United States; Female; Male; Animals; Psychodidae; Ghana; Phlebotomus; DNA; Leishmania
PubMed: 37700879
DOI: 10.1155/2023/1963050 -
PLoS Neglected Tropical Diseases Sep 2023The kala-azar elimination programme has resulted in a significant reduction in visceral leishmaniasis (VL) cases across the Indian Subcontinent. To detect any resurgence...
BACKGROUND
The kala-azar elimination programme has resulted in a significant reduction in visceral leishmaniasis (VL) cases across the Indian Subcontinent. To detect any resurgence of transmission, a sensitive cost-effective surveillance system is required. Molecular xenomonitoring (MX), detection of pathogen DNA/RNA in vectors, provides a proxy of human infection in the lymphatic filariasis elimination programme. To determine whether MX can be used for VL surveillance in a low transmission setting, large numbers of the sand fly vector Phlebotomus argentipes are required. This study will determine the best method for capturing P. argentipes females for MX.
METHODOLOGY/PRINCIPAL FINDINGS
The field study was performed in two programmatic and two non-programmatic villages in Bihar, India. A total of 48 households (12/village) were recruited. Centers for Disease Control and Prevention light traps (CDC-LTs) were compared with Improved Prokopack (PKP) and mechanical vacuum aspirators (MVA) using standardised methods. Four 12x12 Latin squares, 576 collections, were attempted (12/house, 144/village,192/method). Molecular analyses of collections were conducted to confirm identification of P. argentipes and to detect human and Leishmania DNA. Operational factors, such as time burden, acceptance to householders and RNA preservation, were also considered. A total of 562 collections (97.7%) were completed with 6,809 sand flies captured. Females comprised 49.0% of captures, of which 1,934 (57.9%) were identified as P. argentipes. CDC-LTs collected 4.04 times more P. argentipes females than MVA and 3.62 times more than PKP (p<0.0001 for each). Of 21,735 mosquitoes in the same collections, no significant differences between collection methods were observed. CDC-LTs took less time to install and collect than to perform aspirations and their greater yield compensated for increased sorting time. No significant differences in Leishmania RNA detection and quantitation between methods were observed in experimentally infected sand flies maintained in conditions simulating field conditions. CDC-LTs were favoured by householders.
CONCLUSIONS/SIGNIFICANCE
CDC-LTs are the most useful collection tool of those tested for MX surveillance since they collected higher numbers of P. argentipes females without compromising mosquito captures or the preservation of RNA. However, capture rates are still low.
Topics: United States; Female; Humans; Animals; Male; Phlebotomus; Psychodidae; Leishmaniasis, Visceral; Mosquito Vectors; Culicidae; RNA
PubMed: 37656745
DOI: 10.1371/journal.pntd.0011200 -
Parasites & Vectors Aug 2023Blood-sucking phlebotomine sand flies are vectors of the protozoan parasites Leishmania spp. Although the intestinal microbiota is involved in a wide range of biological...
BACKGROUND
Blood-sucking phlebotomine sand flies are vectors of the protozoan parasites Leishmania spp. Although the intestinal microbiota is involved in a wide range of biological and physiological processes and has the potential to alter vector competence, little is known about the factors that modify the gut microbiota composition of sand flies. As a key step toward addressing this issue, we investigated the impact of host species on the gut bacterial composition in Phlebotomus and Lutzomyia sand flies reared under the same conditions.
METHODS
Bacterial 16S rRNA gene amplification and Illumina MiSeq sequencing were used to characterize the overall bacterial composition of three laboratory-reared sandflies: Phlebotomus papatasi, Ph. duboscqi, and Lutzomyia longipalpis.
RESULTS
Our results showed that the larvae of the three sand fly species harbored almost the same microbes but had different relative abundances. Adult Ph. papatasi and Ph. duboscqi revealed similar microbiome compositions, which were distinct from that of adult Lu. longipalpis. Furthermore, we showed that Ph. papatasi and Ph. duboscqi are hosts for different bacterial genera. The experiment was repeated twice to improve accuracy and increase reliability of the data, and the same results were obtained even when a distinct composition of the microbiome among the same species was identified probably because of the use of different larvae food batch.
CONCLUSIONS
The present study provides key insights into the role of host species in the gut microbial content of different sand fly species reared under the same conditions, which may influence their susceptibility to Leishmania infection.
Topics: Animals; Phlebotomus; Psychodidae; RNA, Ribosomal, 16S; Reproducibility of Results; Microbiota; Larva
PubMed: 37653518
DOI: 10.1186/s13071-023-05939-2 -
Parasites & Vectors Aug 2023The successful use of semiochemicals to attract insects to traps is based on research on the most suitable compounds and their release profiles over time. Based on the...
BACKGROUND
The successful use of semiochemicals to attract insects to traps is based on research on the most suitable compounds and their release profiles over time. Based on the group's promising results, matrices with a more adequate release profile and more eco-friendly properties for the release of 1-hexanol were developed. To use a more suitable prototype in the field, the most promising systems were added to a capsule and evaluated in a wind tunnel. Behavioral experiments were performed using the sand fly species, Lutzomyia longipalpis, to evaluate the efficacy of the proposed system.
METHODS
Different delivery systems were developed by varying the polymer (gellan gum and pectin) ratio, crosslinker (aluminum chloride) concentration, and glutaraldehyde removal.The delivery systems were loaded with 1-hexanol, and their release profiles were evaluated using gravimetric analysis under ambient and high-humidity conditions. When the matrix system was placed inside a plastic container, modulations in the active release profile were observed and the system could be reused. Actid attraction behaviors of the sand fly species, Lu. longipalpis, were evaluated in a wind tunnel when exposed to 1-hexanol-loaded release systems at different times.
RESULTS
Among the four formulations evaluated, System 2 (gellan gum and pectin in a 1:1 ratio with 5% aluminum chloride) exhibited the most promising release profile, with greater uniformity and longer compound release time. The maximum 1-hexanol release uniformity was achieved over a longer time, mainly every 24 h, under both ambient and high-humidity conditions. System 2 can be reused at least once with the same structure. The wind tunnel trials exhibited efficient activation and attraction of Lu. longipalpis to 1-hexanol after 24, 48, and 72 h in System 2 placed inside the capsules.
CONCLUSIONS
The polymeric matrix supplemented with 1-hexanol and introduced in plastic capsules showed promising results in attracting sand flies. This system can be used as a solution for other attractive compounds as well as in other applications where their release needs to be controlled or prolonged.
Topics: Animals; Psychodidae; Aluminum Chloride; Capsules; Polymers; Phlebotomus; Plastics; Pectins
PubMed: 37644584
DOI: 10.1186/s13071-023-05931-w -
The American Journal of Tropical... Oct 2023We used spatial analysis tools to examine the epidemiological situation and spatial distribution of American tegumentary leishmaniasis in the municipality of Caratinga...
We used spatial analysis tools to examine the epidemiological situation and spatial distribution of American tegumentary leishmaniasis in the municipality of Caratinga between 2016 and 2021. In addition, potential sandfly vectors were captured. All information used in this study was retrieved from public health archives and confirmed in the state health services databases. All cases were analyzed using Geographic Information Systems software. In addition, sandfly collections and molecular detection of Leishmania were carried out in areas with the highest number of cases. During the analyzed period, American tegumentary leishmaniasis (ATL) cases increased and remained high in the last years. The hotspots included urban areas of Caratinga city and the districts of Patrocínio of Caratinga and Sapucaia. The species Nyssomyia whitmani, Nyssomyia intermedia, and Migonemyia migonei were the most abundant species and the ITS1-polymerase chain reaction technique detected Leishmania DNA in these species. On the basis of our analyses, the urbanization of ATL in Caratinga has taken place in recent years. Because of the increase in the number of human cases and the presence of vectors, it is recommended that health authorities focus on control measures in hotspots.
Topics: Animals; Humans; Brazil; Insect Vectors; Leishmaniasis, Cutaneous; Leishmania; Psychodidae; Phlebotomus
PubMed: 37640295
DOI: 10.4269/ajtmh.23-0017 -
Biomolecules Aug 2023Sand flies (Diptera: Psychodidae) serve as vectors for transmitting protozoan parasites, spp., that cause the disease called leishmaniasis. The main approach to...
Sand flies (Diptera: Psychodidae) serve as vectors for transmitting protozoan parasites, spp., that cause the disease called leishmaniasis. The main approach to controlling sand flies is the use of chemical insecticides. The discovery of alternative methods for their control is needed because of potential health risks of chemical insecticides and development of sand fly resistance to these pesticides. The biomineral produced by diatoms (diatomaceous earth, DE; Celite) and a volcanic glass bio-mimic (Imergard) have been shown by our group to be efficacious against mosquitoes, filth flies, and ticks but never studied for the control of sand flies. In a modified World Health Organization cone test, 50% of adult sand flies at 29 ± 1 °C, 55 ± 5% RH, and 12:12 LD, when exposed to Imergard and Celite, were dead in 13.08 and 7.57 h, respectively. Proof of concept was established for the use of these biominerals for sand fly and leishmaniasis disease control. Using a light source as an attractant to the minerals had no significant effect on the LT, the time to 50% mortality. The LT at a higher relative humidity of 70 ± 5% increased to 20.91 and 20.56 h for Imergard and Celite, respectively, suggesting their mode of action was dehydration. Scanning electron microscopy of dead sand flies showed high coating levels of Celite only on the sides of the thorax and on the tarsi, suggesting an alternative mode of action for mechanical insecticides.
Topics: Animals; Diatomaceous Earth; Insecticides; Leishmania; Minerals; Parasites; Psychodidae
PubMed: 37627300
DOI: 10.3390/biom13081235 -
Medecine Tropicale Et Sante... Jun 2023To attempt resolving this issue accurately, it was necessary to anchor our experimental approaches in the observations and pioneering work of our predecessors, notably...
To attempt resolving this issue accurately, it was necessary to anchor our experimental approaches in the observations and pioneering work of our predecessors, notably Alphonse Laveran, Louis Parrot, Edmond and Étienne Sergent. The latter, among other things, had identified as natural hosts of leishmaniasis, rodent populations with which hematophagous telmophagous sand fly populations cohabited closely.When human populations emerged in these natural ecosystems, after the sedentarization of more or less important disturbances would have led to a transition of sand fly hematophagy, from zoophilia, to zoo-anthropophilia and anthropophilia.The creation of infrastructures that allow the breeding and integration into experimental groups of both holobiont sand flies and holobiont laboratory rodents (rats, mice, hamsters, etc.) remains crucial. With such infrastructures, it becomes possible to grasp and characterize the multilateral dynamic processes - mostly clinically silent - that account for the biogenesis of tissue and/or cellular niches protecting populations of developmental morphotypes, including those ensuring host-to-host transmission, albeit in small numbers.
Topics: Cricetinae; Humans; Mice; Rats; Animals; Leishmania; Ecosystem; Leishmaniasis; Phlebotomus; Psychodidae; Rodentia
PubMed: 37525683
DOI: 10.48327/mtsi.v3i2.2023.384 -
Parasites & Vectors Jul 2023Phlebotomine sand flies of the genus Trichophoromyia Barretto, 1962 are of great relevance to public health as vectors of Leishmania protozoans. A new phlebotomine...
BACKGROUND
Phlebotomine sand flies of the genus Trichophoromyia Barretto, 1962 are of great relevance to public health as vectors of Leishmania protozoans. A new phlebotomine species named Trichophoromyia peixotoi n. sp. is here described based on both male morphology and COI DNA barcodes.
METHODS
The sand fly specimens were collected in the Parque Nacional da Amazônia (PNA), situated in the municipality of Itaituba, state of Pará, Brazil. Morphological description was done based on 10 male specimens. Five specimens were DNA barcoded for the COI gene.
RESULTS
The morphological and molecular analyses allowed the delimitation of this new species from others of Trichophoromyia. Trichophoromyia peixotoi n. sp. is closely related to other species with aedeagal ducts > 4 times the length of the sperm pump, from which it may be distinguished by the gonocoxite bristles and paramere shape.
CONCLUSIONS
The description of T. peixotoi n. sp. brings the number of species of Trichophoromyia to 45, including 24 for Brazil. The integrative taxonomy effort through the analysis of COI barcodes proved to be effective in the species delimitation of some Trichophoromyia spp.
Topics: Animals; Male; Psychodidae; Brazil; Semen; Phlebotomus; DNA
PubMed: 37468935
DOI: 10.1186/s13071-023-05850-w -
Revista Brasileira de Parasitologia... 2023The objective was to study the composition of sand fly species, the seasonal activity of the dominant species and correlation with average rainfall, sex association of...
The objective was to study the composition of sand fly species, the seasonal activity of the dominant species and correlation with average rainfall, sex association of the dominant species with domicile habitats and analyze different landscape scenarios for the two study sites in the municipalities of Itapevi and Mogi of the Crosses. Sandflies were captured with CDC(s) traps installed in three households at each study site for a period of 24 hours, biweekly for two years. A total of 2970 specimens were collected. The dominant species were P.fischeri and M.migonei. A statistically significant difference was registered between males and females of the two species in relation to the intra and peridomicile. The seasonal activity of both species showed a weak significant positive correlation with rainfall. The species P.fischeri and M.migonei may be potential vectors of CVL in the studied sites.
Topics: Male; Female; Animals; Dogs; Leishmaniasis, Visceral; Cities; Brazil; Psychodidae; Phlebotomus; Leishmaniasis, Cutaneous; Dog Diseases
PubMed: 37466624
DOI: 10.1590/S1984-29612023040 -
PloS One 2023Phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae) have biological relevance as vectors of several pathogens. To ensure periodic entomological monitoring it...
Phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae) have biological relevance as vectors of several pathogens. To ensure periodic entomological monitoring it is necessary to have efficient and accurate tools for an adequate taxonomic identification. There are only few studies on phylogenetic analyses of phlebotomine sand flies from Neotropics, based mostly on morphological and/or molecular data, which makes the delimitation of intra- and interspecific variability of species challenging. Here we generated new molecular information on sand fly species distributed in endemic areas of leishmaniasis in Mexico, using mitochondrial and ribosomal genes, and incorporating morphological information available. Specifically, we established their phylogenetic relationships, and estimated their divergence time. Our study provides molecular information for 15 phlebotomine sand fly species from different areas of Mexico, contributing to the genetic inventory and phylogenetic relations among Neotropical species of the subfamily Phlebotominae. Mitochondrial genes proved to be suitable markers for the molecular identification of phlebotomine sand flies. However, the incorporation of additional nuclear gene information could increase the significance of phylogenetic inferences. We also provided evidence about a possible divergence time of phlebotomine sand fly species, supporting their presumable origin in the Cretaceous period.
Topics: Animals; Psychodidae; Phylogeny; Mexico; Phlebotomus; Genes, Mitochondrial
PubMed: 37384618
DOI: 10.1371/journal.pone.0287853