Breeding Sites Of Sand Flies Research Articles

Soil Analysis of Potential Breeding Sites of Sand Flies (Diptera: Psychodidae) in Aichoun Locality, Central Morocco

The epidemiology of leishmaniasis is related with habitat and behavior of the sand fly vector. Each species of sand flies (Diptera: Psychodidae) has a specific characteristic of their sites for the development of their immatures. Information on natural breeding sites of phlebotomine sand flies is limited, due to the difficulty of isolation of immature from the soil. This study, realized from May 2014 to September 2014, aimed to determine the effect of properties of soil on behavior and abundance of sand flies in breeding habitat in Aichoun locality. Sand flies were collected using sticky papers (21 × 27.3 cm) coated with castor oil in four stations. The total of traps in each trapping campaign is 32. Soil samples were collected each month and they were extracted and tested. The different chemical parameters have been studied: electrical conductivity, equivalent humidity, total of calcareous, organic matter, assimilable phosphorus, and exchangeable potassium, pH, organic carbon. Statistical analysis was performed by principal component analysis (PCA). The dominant leishmaniasis vectors in Aichoun are Phlebotomus sergenti and Phlebotomus perniciosus. A total of 1685 sand flies were collected belonging to five species in the genera Phlebotomus and Sergentomyia, namely Ph. sergenti (84.62%), Ph. perniciosus (8.54%), Phlebotomus papatasi (6.17%), Phlebotomus longicuspis (0.35%) and Sergentomyia minuta (0.29%). The chemical tests of potential breeding sites of sand flies, determined for sixteen samples, showed a correlation between the abundance of sand flies (especially the ecological requirements of larval development of the three species incriminated in transmission of the disease of cutaneous leishmaniasis) and the chemical parameters studied. The results found in this work, realized for the first time in Morocco, will be of great contribution to the control program of sand flies vectors at local and national level and as an indicator for the determination of leishmaniasis risk areas as well as to establish effective control strategies.

Potential Resting and Breeding Sites of Sand Flies (Diptera: Psychodidae) and Their Habitat Characteristics in Leishmaniasis Foci of Dir Districts, Khyber Pakhtunkhwa, Pakistan.

Despite their medical importance, natural breeding sites of sand flies have been poorly explored. Detecting such sites is imperative in vector control strategies. This study aimed to identify potential breeding and resting microhabitats of sand flies and household risk factors associated with cutaneous leishmaniasis transmission in Dir districts, Khyber Pakhtunkhwa, Pakistan. Survey of indoor and outdoor habitats in four tehsils (subdistricts) of upper and lower Dir districts was carried out using sticky traps, flit method, and aspirator. To assess risk factors associated with cutaneous leishmaniasis (CL), questionnaires were administered to household heads. Mud houses and plants belonging to Cucurbitaceae family sheltered highest number of sand flies. Excessive number of flies were collected from indoor sites (common rooms used for both people and animals) compared to outdoor habitats (cattle dungs). Phlebotomus salangensis Artemiev, 1978 and Phlebotomus sergenti were the most widely distributed species, while Sergentomyia bailyi peaked in caves with high organic content in soil. Roof material and ownership of fans were associated with significant risk of CL. Findings of this study present a list of potential breeding sites for sand flies and CL risk factors that can be targeted and implemented in control programs for CL. Further studies are required to elucidate the breeding behavior and preferences of these medically important vectors.

Study on natural breeding sites of sand flies (Diptera: Phlebotominae) in areas of Leishmania transmission in Colombia.

BackgroundThe location of the microhabitats where immature phlebotomine sand flies of the genus Lutzomyia develop is one of the least-known aspects of this group of medically important insects. For this reason strategies of source reduction approach for their control have not been possible in contrast to other insect vectors (such as mosquitoes), because their juvenile stages in terrestrial microhabitats is difficult to detect.MethodsDirect examination of soil samples, incubation of substrates and the use of emergence traps were the methods used to identify juvenile stages in 160 soil samples from urban and forest habitats within the foci of Leishmania transmission in Colombia. Immatures collected were identified subsequent from the rearing and emergence of adults using taxonomic keys or the analysis of the mitochondrial marker cytochrome oxidase I. Plant species associated with the natural breeding sites were identified and physicochemical properties of the soils were analyzed.ResultsA total of 38 (23.7%) sampling sites were identified as breeding sites, 142 phlebotomine sand flies were identified, belonging to 13 species of the genus Lutzomyia and two of Brumptomyia. The greatest numbers of immature were found within the tabular roots (51 immature sand flies from eight positive sites) and bases of trees (35 immature sand flies from 11 sites). The characterization and presence of the tree species (mainly Ceiba pentadra, Anacardium excelsum, Pseudosamanea guachapale) and the physicochemical properties (relative humidity and carbon/nitrogen ratio) of the soils associated with these breeding sites are significant factors in explaining the diversity and abundance of phlebotomine sand flies.ConclusionsImmature phlebotomine sand flies of the genus Lutzomyia in Colombia can be found in a wide variety of breeding sites rich in organic matter, high relative humidity and are associated with a typical vegetation of each locality. These results provide new perspectives for the study of the ecology of the genus Lutzomyia in Colombia and the development of vector control strategies.

Natural breeding sites of phlebotomine sand flies (Diptera: Psychodidae) on Marambaia Island, Rio de Janeiro State, Brazil

Immature phlebotomine sand flies develop in soils with essential and ideal characteristics for their life cycle, such as organic matter, humidity, temperature and low levels of light. Information regarding the potential breeding places of these dipterans is fundamental to understand the epidemiology and ecology of leishmaniasis, in addition to its importance to control them. In the present study, we aimed to find natural breeding sites of sand flies on Marambaia Island with the aid of emergence traps and direct search of immature forms using the flotation technique with saturated sugar solution in organic substrates of the region. Both methods were effective, with a total of 42 specimens of six different species – including some species that participate in the transmission cycle of American Tegumentary Leishmaniasis – collected by the emergence traps, and five immature forms obtained by floatation technique. However, further studies are still necessary, mainly with respect to the ecology and biology of immature sandfly stages, so that control measures focused on breeding sites can produce positive sustainable results in natural environments.

Control of phlebotomine sandflies.

Phlebotomine sandflies (Diptera: Psychodidae) transmit many zoonotic diseases (arboviruses, bartonelloses and especially leishmaniases) of importance to human health in at least 80 countries. Measures used to control adult sandflies (Lutzomyia and Phlebotomus) include the use of insecticides (mostly pyrethroids) for residual spraying of dwellings and animal shelters, space-spraying, insecticide-treated nets, impregnated dog-collars and personal protection through application of repellents/insecticides to skin or fabrics. Because the breeding-sites of sandflies are generally unknown, control measures that act specifically against immatures are not feasible, although the effectiveness of a few biological and chemical agents has been demonstrated in laboratory evaluations. Reports of insecticide-resistance refer to only three sandfly species (P. papatasi, P. argentipes and S. shorttii) against DDT in one country (India), although there are reports of DDT-tolerance in several countries. Current knowledge of sandfly susceptibility to various insecticides is summarized. Constraints and advantages of different compounds, formulations and delivery methods for sandfly control under different environmental conditions are discussed.