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

Abstract

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.