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Journal of Vector Borne Diseases Apr 2024Leishmaniasis is caused by various species of parasite Leishmania. Approximately twenty of them are pathogenic to mammals. In Sri Lanka, cutaneous leishmaniasis (CL) is...
BACKGROUND OBJECTIVES
Leishmaniasis is caused by various species of parasite Leishmania. Approximately twenty of them are pathogenic to mammals. In Sri Lanka, cutaneous leishmaniasis (CL) is an established vector-borne disease. CL originates and spreads mainly through sandfly bite in many endemic countries. The aim of the present study was to compare the geographical distribution and demographic features of CL cases in Hambantota district, Sri Lanka in 2014 and 2016.
METHODS
The patients who were presented to the Tangalle Base Hospital from June to December in 2014 and 2016 were examined and a descriptive study was carried out using a structured-questionnaire. Slit-skin smears were collected from each patient, Giemsa-stained and examined under the light microscope to identify Leishmania amastigotes.
RESULTS
Out of 256 and 314 suspected CL patients, 156 and 155 were identified positive for the year 2014 and 2016, respectively. Out of 12 District Secretary Divisions (DSD) in Hambantota district, the highest number of CL cases, 85 and 86 was reported from Tangalle DSD in 2014 and 2016 respectively. Number of identified CL patients in Beliatta DSD had increased from 50 to 67 during the study period. In both years, majority of CL patients were ≥50 years old with males more infected than females. Although CL association with occupations were insignificant, housewives were the highly (23%) infected occupants in this area.
INTERPRETATION CONCLUSION
Based on the present findings, geographical distribution within DSDs in Hambantota district had changed. This emphasizes the importance of CL as a health problem in Hambantota district.
Topics: Leishmaniasis, Cutaneous; Humans; Sri Lanka; Male; Female; Middle Aged; Adult; Adolescent; Young Adult; Child; Aged; Child, Preschool; Leishmania; Animals; Surveys and Questionnaires; Aged, 80 and over; Psychodidae; Infant
PubMed: 38922662
DOI: 10.4103/jvbd.jvbd_117_23 -
Journal of Vector Borne Diseases Apr 2024Sandflies are vector insects associated with terrestrial forest ecosystems; in the Ecuadorian Andes, they participate in the transmission of human cutaneous...
BACKGROUND OBJECTIVES
Sandflies are vector insects associated with terrestrial forest ecosystems; in the Ecuadorian Andes, they participate in the transmission of human cutaneous leishmaniasis. This geographical area represents an opportunity to evaluate the role of sandflies as bioindicators of the degree of intervention of tropical humid forest ecosystems (THF) associated with changes in the ecology of the local landscape.
METHODS
CDC-light traps were used for collecting adult sandflies in February 2020 in a humid tropical forest within the Chocó Biosphere Reserve. All species were identified using morphological keys. Analysis data about abundance, richness, species accumulation, diversity index, species composition communities, species sex proportion, spatial sandflies environmental, Renyi's Diversity Profile were performed to compare six spatial habitats in Mashpi locality, Ecuador.
RESULTS
Sandflies were collected (n-1435); the main species are represented by Trichophoromyia reburra, Nyssomyia trapidoi, Psathyromyia aclydifera, Psychodopygus panamensis and Lutzomyia hartmanni. Only Th. reburra is associated with not intervened forest, while the other three species are associated with intervened forest within Mashpi in the Choco Biosphere Reserve. The secondary forest has major sandflies' richness, while the primary forest exhibits major abundance.
INTERPRETATION CONCLUSION
Th. reburra is a sandfly restricted to the Andean Forest and is a bioindicator of the high environmental health quality of the forest, while Ny. trapidoi and Pa. aclydifera are bioindicators of environmental disturbances in the forest. Additionally, Ps. panamensis, Lu. hartmanni and Ny. trapidoi are bioindicators of human impact and the risk of leishmaniasis.
Topics: Animals; Psychodidae; Forests; Insect Vectors; Ecuador; Ecosystem; Male; Female; Leishmaniasis, Cutaneous; Biodiversity; Humans
PubMed: 38922658
DOI: 10.4103/jvbd.jvbd_52_23 -
Parasites & Vectors Jun 2024The sand fly Nyssomyia neivai is one of the most abundant species in Southern Brazil. It is frequently found in areas that are foci of visceral leishmaniasis in the...
BACKGROUND
The sand fly Nyssomyia neivai is one of the most abundant species in Southern Brazil. It is frequently found in areas that are foci of visceral leishmaniasis in the state of Santa Catarina, caused by Leishmania infantum. In this region, the main vector of L. infantum, Lutzomyia longipalpis, has not been detected. In the absence of L. longipalpis, this study aimed to identify the sand fly fauna and diagnose any potential Leishmania spp. infection in sand flies and in dogs in a region of Southern Brazil that experienced a recent canine visceral leishmaniasis outbreak.
METHODS
This report includes a survey of the sand fly fauna at the Zoonosis Control Center of the Municipality of Tubarão (Santa Catarina, Brazil). Molecular tests were conducted to investigate Leishmania spp. natural infection in sand flies using polymerase chain reaction (PCR). In positive females, in addition to morphological identification, molecular analysis through DNA barcoding was performed to determine the sand fly species. Additionally, the dogs were tested for the presence of Leishmania spp. using a non-invasive technique for the collection of biological material, to be assessed by PCR.
RESULTS
A total of 3419 sand flies, belonging to five genera, were collected. Nyssomyia neivai was the most abundant species (85.8%), followed by Migonemyia migonei (13.3%), Pintomyia fischeri (0.8%), Evandromyia edwardsi (< 0.1%), and species of the genus Brumptomyia. (0.1%). Out of the 509 non-engorged females analyzed by PCR, two (0.4%) carried L. infantum DNA. The naturally infected females were identified as Ny. neivai, in both morphological and molecular analysis. In addition, two out of 47 conjunctival swabs from dogs tested positive for L. infantum, yielding an infection rate of 4.2%.
CONCLUSIONS
These results confirm the presence of Ny. neivai naturally infected with L. infantum in an area where dogs were also infected by the parasite, suggesting its potential role as a vector in Southern Brazil.
Topics: Animals; Dogs; Leishmania infantum; Brazil; Psychodidae; Dog Diseases; Leishmaniasis, Visceral; Female; Insect Vectors; Polymerase Chain Reaction; Male
PubMed: 38918858
DOI: 10.1186/s13071-024-06336-z -
Revista Da Sociedade Brasileira de... 2024Pressatia choti is a common sand fly found in the Atlantic Forest of Brazil, which is suspected to be involved in the transmission of Leishmania braziliensis. Herein, we...
BACKGROUND
Pressatia choti is a common sand fly found in the Atlantic Forest of Brazil, which is suspected to be involved in the transmission of Leishmania braziliensis. Herein, we aimed to establish a Pr. choti laboratory colony.
METHODS
Wild-caught female sand flies were blood fed on hamsters and maintained under controlled conditions (temperature: 26 °C; relative humidity: 70%).
RESULTS
Of the 301 collected female sandflies, 288 were identified as Pr. choti. The life cycle duration ranged from 31 to 56 days.
CONCLUSIONS
We successfully established a Pr. choti colony, whose biological parameters were similar to those of other neotropical sand flies.
Topics: Animals; Psychodidae; Leishmania braziliensis; Female; Insect Vectors; Brazil; Cricetinae
PubMed: 38896655
DOI: 10.1590/0037-8682-0060-2024 -
PLoS Neglected Tropical Diseases Jun 2024Leishmaniasis, a neglected disease and public health concern, is associated with various factors such as biological, social, economical conditions and climate,...
BACKGROUND
Leishmaniasis, a neglected disease and public health concern, is associated with various factors such as biological, social, economical conditions and climate, increasing the risk of human infection. Understanding the population dynamics of the vectors, like Pintomyia longiflocosa, and its relationship with ecological variables is crucial for developing effective strategies to control sand fly populations and combat cutaneous leishmaniasis in a tropical country like Colombia.
METHODOLOGY
Adult sand flies were collected in three different sample locations: outdoor, indoor, and peri-domestic areas in three houses located in the rural settlement of Campoalegre (Huila) between February 2020 and February 2021, using the CDC light traps. The sand fly density was quantified and associated with the sample locations and the sampling months using Analysis of Variance and Pearson correlations.
PRINCIPAL FINDINGS
In the period of the sample, 98.86% of sand fly collected was identified as Pi. longiflocosa. The density of this species was significantly different between males and females, the latter contributing more to density in all sample locations (P<0.0001). The outdoor was the sample location with the highest and most significative density in this study (70%, P = 0.04). The density of these sand flies is related to the seasonality of Campoalegre, revealing a density peak from February and June to October (P < 0.05). Finally, precipitation is the environmental variable prominently linked to the density pattern, showing a negative correlation with it. Months with the highest precipitations show the lowest values of Pi. longiflocosa abundance.
CONCLUSIONS/SIGNICANCE
Our investigation reveals a inverse correlation between precipitation levels and the abundance of Pi. longiflocosa in Campoalegre (Huila), particularly in outdoor areas. This suggests that vector control strategies to periods of reduced precipitation in outdoor settings could offer an effective approach to minimizing cases of cutaneous leishmaniasis in the region.
Topics: Animals; Leishmaniasis, Cutaneous; Colombia; Psychodidae; Insect Vectors; Female; Male; Humans; Seasons; Population Dynamics; Spatio-Temporal Analysis
PubMed: 38885272
DOI: 10.1371/journal.pntd.0012237 -
Biodiversity Data Journal 2024Our study aimed to develop an optimised laboratory protocol ensuring the preservation of morphological structures and extraction of high-quality DNA sequences from...
Our study aimed to develop an optimised laboratory protocol ensuring the preservation of morphological structures and extraction of high-quality DNA sequences from Psychodidae (Insecta, Diptera) specimens. With 310 analysed specimens, we investigated the impact of distinct laboratory treatments by employing two shaking categories (constant and interrupted) with five different incubation periods (16, 12, 8, 4 and 2 hours) during the DNA extraction process. Notably, 80.65% of the specimens exhibited morphological changes during DNA extraction. Our results indicated no statistical difference between constant and interrupted shaking for the total of morphological structures lost. However, within each shaking category, the loss of structures was influenced significantly by the incubation period. Prolonged incubation correlated with increased structural losses, whereas shorter incubation periods caused minor alterations in structures lost. In addition, our results showed a significant difference between constant and interrupted shaking treatments for DNA concentration. Likewise, the incubation period showed differences within each shaking category. Successful COI sequencing was achieved in 89.6% of specimens, with negligible differences in DNA fragment lengths across treatments. Our findings underscore the importance of an optimised protocol and its potential in systematic research involving nematoceran dipteran specimens by balancing morphological integrity and DNA extraction efficiency.
PubMed: 38883206
DOI: 10.3897/BDJ.12.e119448 -
Journal of Arthropod-borne Diseases Dec 2023(Diptera: Psychodidae) is the main vector of zoonotic cutaneous leishmaniasis (ZCL) in Iran. The nonstandard use of pesticides against pests, particularly in...
BACKGROUND
(Diptera: Psychodidae) is the main vector of zoonotic cutaneous leishmaniasis (ZCL) in Iran. The nonstandard use of pesticides against pests, particularly in agriculture, indirectly has caused the development of resistance and, consequently, the threat of control measures in ZCL endemic areas. Up to 2023, several reports of resistance in have been declared in the Old World. The purpose of this study was to measure the lethal time (LT and LT) of sand flies in the ZCL endemic center of Esfahan to DDT and deltamethrin insecticides.
METHODS
Sand flies were collected in Borkhar and were tested using WHO adult mosquito test kit against DDT 4% and deltamethrin 0.0002%. The and fly's survival was recorded during exposure time in 225, 450|, 900, 1800, and 3600-seconds' intervals for DDT and Deltamethrin and they were allowed to recover for 24 hours. Then LT and LT were analyzed using probit software. were identified using morphological keys and other sand flies' species were excluded from the analysis.
RESULTS
The insecticide against female revealed hundred percent mortality when exposed to DDT 4% and deltamethrin 0.0002%. The LT and LT were 19.32 and 22.74 minutes for DDT 4% and 39.92 and 51.33 minutes for deltamethrin 0.0002% respectively.
CONCLUSION
Results of this study revealed that is still susceptible to DDT and deltamethrin. This data provides valuable knowledge to implement effective control strategies against ZCL main vector and help to manage insecticide resistance in the region.
PubMed: 38868678
DOI: 10.18502/jad.v17i4.15296 -
Journal of Arthropod-borne Diseases Sep 2023Zoonotic cutaneous leishmaniasis is a major public health problem in Iran with the main vector of . The use of entomopathogenic fungi for biological control of the...
BACKGROUND
Zoonotic cutaneous leishmaniasis is a major public health problem in Iran with the main vector of . The use of entomopathogenic fungi for biological control of the vector is a potential substitute for the current methods which are being used. The purpose of the current study was to assess the virulence of two local isolates of (OZ and TV) against .
METHODS
To perform the bioassay test, fungal suspensions were applied for every stage of the sand fly life cycle. The mortality rate, longevity, and number of eggs laid were determined. Also, the probability of fungal survival on the surface of rodent's body was assessed.
RESULTS
The longevity of infected adult sand flies with both isolates of was significantly lower (P< 0.05) in comparison to the negative control. The estimated Lethal concentration 50 (LC) values for adult female and male sand flies treated with OZ isolate were 1.4×10 and 2.2×10 conidia/ml, respectively, while they were 6.8×10 and 2.3×10 conidia/ml for TV isolate, respectively. Both isolates of exhibited nonsignificant mortality rates in sand fly larvae and pupae and fecundity rate (P> 0.05). According to our findings for both isolates, the fungus continued to spread throughout the surface of the rodent's body for 144 hours after spraying.
CONCLUSION
The current study demonstrated that both isolates of have considerable biological control capacity against adult sand flies.
PubMed: 38860196
DOI: 10.18502/jad.v17i3.14986 -
Parasites & Vectors Jun 2024Arthropods vector a multitude of human disease-causing organisms, and their geographic ranges are shifting rapidly in response to changing climatic conditions. This is,...
BACKGROUND
Arthropods vector a multitude of human disease-causing organisms, and their geographic ranges are shifting rapidly in response to changing climatic conditions. This is, in turn, altering the landscape of disease risk for human populations that are brought into novel contact with the vectors and the diseases they carry. Sand flies in the genera Lutzomyia and Pintomyia are vectors of serious disease-causing agents such as Leishmania (the etiological agent of leishmaniasis) and may be expanding their range in the face of climate change. Understanding the climatic conditions that vector species both tolerate physiologically and prefer behaviorally is critical to predicting the direction and magnitude of range expansions and the resulting impacts on human health. Temperature and humidity are key factors that determine the geographic extent of many arthropods, including vector species.
METHODS
We characterized the habitat of two species of sand flies, Lutzomyia longipalpis and Pintomyia evansi. Additionally, we studied two behavioral factors of thermal fitness-thermal and humidity preference in two species of sand flies alongside a key aspect of physiological tolerance-desiccation resistance.
RESULTS
We found that Lu. longipalpis is found at cooler and drier conditions than Pi. evansi. Our results also show significant interspecific differences in both behavioral traits, with Pi. evansi preferring warmer, more humid conditions than Lu. longipalpis. Finally, we found that Lu. longipalpis shows greater tolerance to extreme low humidity, and that this is especially pronounced in males of the species.
CONCLUSIONS
Taken together, our results suggest that temperature and humidity conditions are key aspects of the climatic niche of Lutzomyia and Pintomyia sand flies and underscore the value of integrative studies of climatic tolerance and preference in vector biology.
Topics: Animals; Psychodidae; Humidity; Temperature; Female; Male; Ecosystem; Insect Vectors
PubMed: 38831449
DOI: 10.1186/s13071-024-06325-2 -
PLoS Neglected Tropical Diseases May 2024
Topics: Leishmania tropica; Animals; Phlebotomus; Salivary Proteins and Peptides; Plasmids; Insect Proteins; Mice; Humans; Leishmaniasis, Cutaneous; Female
PubMed: 38814961
DOI: 10.1371/journal.pntd.0012218