Plant-feeding phlebotomine sand flies, vectors of leishmaniasis, preferCannabis sativa

Abstract

Blood-sucking phlebotomine sand flies (Diptera: Psychodidae) transmit leishmaniasis as well as arboviral diseases and bartonellosis. Sand fly females become infected withLeishmaniaparasites and transmit them while imbibing vertebrates’ blood, required as a source of protein for maturation of eggs. In addition, both females and males consume plant-derived sugar meals as a source of energy. Plant meals may comprise sugary solutions such as nectar or honeydew (secreted by plant-sucking homopteran insects), as well as phloem sap that sand flies obtain by piercing leaves and stems with their needle-like mouthparts. Hence, the structure of plant communities can influence the distribution and epidemiology of leishmaniasis. We designed a next-generation sequencing (NGS)–based assay for determining the source of sand fly plant meals, based upon the chloroplast DNA gene ribulose bisphosphate carboxylase large chain (rbcL). Here, we report on the predilection of several sand fly species, vectors of leishmaniasis in different parts of the world, for feeding onCannabis sativa. We infer this preference based on the substantial percentage of sand flies that had fed onC. sativaplants despite the apparent “absence” of these plants from most of the field sites. We discuss the conceivable implications of the affinity of sand flies forC. sativaon their vectorial capacity forLeishmaniaand the putative exploitation of their attraction toC. sativafor the control of sand fly-borne diseases.