**7. EVs in promoting infectious disease**

Protozoan parasites such as Leishmania, Plasmodium, and Toxoplasma contribute to significant morbidity and mortality in humans. Studies have shown EVs can modulate host immune cells [37]. *Leishmania* parasites are transmitted by sandflies and are responsible for infecting phagocytic cells inside the mammalian host. A study by Atayde et al. showed exosomes secreted within the midgut of *L. major* parasites enhance infection and contribute to the development of lesions after being injected in mice [38]. *Plasmodium* parasites are the etiological agents of malaria. Multiple studies have demonstrated an important role for EVs in *Plasmodium* infections. One study showed malaria-infected red blood cells use exosome-like vesicles to communicate which promotes differentiation to sexual forms [39]. Another study showed malaria antigens are enriched in microvesicles released from infected red blood cells which activate host monocytes and neutrophils [40]. *Toxoplasma* is acquired by ingestion of raw or uncooked meat and these parasites are common in virtually all species of warm-blooded vertebrates. Li et al. performed an analysis of differential exosomal miRNAs in dendritic cells induced by Toxoplasma gondii infection [41]. These studies also implicate a role for exosomes in toxoplasmosis and the ability to stimulate naïve recipient cells.
