Exosomes are nano-vesicles measuring 30-100 nm composed of two lipid layers and generated by the endocytosis of plasmatic membrane segments. It is surprising that until recently exosomes were practically unknown, and were thought to be subproducts of cell metabolism. This perception has changed radically, given their newly discovered role as mediators involved in transmitting biological signals, as well as their potential in diagnostics and new therapeutic strategies in cancer and other diseases, including parasitic ones. In this proposal we hypothesise that exosomes deriving from untreated diseases caused by three human parasites, malaria vivax, Chagas and fascioliasis, act as cell intercommunicators facilitating the establishment of infections. Moreover, parasitic proteins in these exosomes will identify new antigens for vaccinations, and the use of exosomes will make it possible to create a new platform of nanovaccines against the aforementioned parasites.