Proteomic Analysis of Urine from Patients with Plasmodium vivax Malaria Unravels a Unique Plasmodium vivax Protein That Is Absent from Plasmodium falciparum.

Five species of Plasmodium cause malaria in humans and two of them, P. vivax and P. falciparum, pose the greatest threat. Rapid antigen detection tests (RADT) have been used for many years to diagnose and distinguish malaria caused by these two parasites. P. falciparum malaria can single-handedly be diagnosed using an RADT, which detects the unique P. falciparum specific histidine-rich protein 2 (HRP2). Unfortunately, there is no RADT that can single-handedly diagnose P. vivax malaria because no specific marker of this parasite has yet been described. Here, we report the discovery of a unique P. vivax protein (Vir14, NCBI Reference Sequence: XP_001612449.1) that has no sequence similarity with proteins of P. falciparum and no significant similarities with proteins of other species of Plasmodium. We propose that this protein could be an outstanding candidate molecule for the development of a promising RADT that can single-handedly and specifically diagnose P. vivax malaria.