Ecology of Leishmaniasis in an urbanized landscape: Relationship of sand fly densities, and Leishmania tropica infection rates with reservoir host colonies

Urbanization may influence the transmission of leishmaniasis, which is as a serious public health issue in Palestine. Semi urban environments can provide suitable habitats for the reservoir host species and the vector sand flies to create favorable condition for disease transmission. This study was aimed to evaluating the effect of distance from hyrax (reservoir host) colonies on sand fly (vector) abundance and its relationship to Leishmania infection within a semi urban landscape. In the Aleskan neighborhood the town of Tubas, sand flies were collected in July and September of 2016. Five trapping transects were set running from a rocky area containing hyrax dwelling habitats into an area of inhabited houses. 1051 Phlebotomus sand flies from 9 species were captured. The numbers of Phlebotomus sergenti, the vector species, correlated negatively with the distance from hyrax. Infected, blood engorged female sand flies were captured closer to hyrax colonies than infected, non-fed females. The risk of disease transmission to humans increased with a high density of reservoirs, closer proximity of reservoir hosts, and high densities of sand flies near houses. These results must be taken into account when implementing future interventions to reduce CL in urban environments.