Figure Legends
Figure 1. Life cycles of zoonotic vs anthroponotic spread of Leishmania spp . Animals depicted have been documented as a blood source in Leishmania positive sand flies.
Figure 2. Distribution of L. donovani complex spp. and different transmission ecologies. AVL= anthroponotic VL, ZVL= zoonotic VL.
Figure 3. The skin as a predominant source forLeishmania parasites in different clinical settings. Sand flies use their serrated proboscis to probe the skin for dermal blood vessels creating a pool of blood from which to feed. Asymptomatic L. donovani infection provides a setting with productive immunity and a relatively low parasite load in the skin and blood. During symptomatic VL, high parasitemia and patches of highly parasitized macrophages in the skin lead to a highly increased chance of sand fly infection during feeding. PKDL is associated with an immune response againstLeishmania parasites in the skin and therefore is characterized by a significant parasite burden within dermal macrophages. After treatment for VL, parasitemia may diminish before parasites in the skin are eradicated. However, patients with both forms of PKDL have been found to be readily infectious to sand fly vectors. Nodular/papular PKDL patients, shown to have significantly increased parasite burden in the skin compared to macular PKDL, are more infectious to sand flies than macular PKDL patients.