Plasmodium vivax is one of the species of Plasmodium parasites that cause malaria in humans. It is a significant cause of malaria outside Africa, especially in Asia and Latin America. Unlike Plasmodium falciparum, which is responsible for most malaria deaths worldwide, P. vivax tends to cause a less severe form of the disease. However, Plasmodium vivax infections can still be debilitating and cause severe health issues, including anemia and spleen enlargement. Plasmodium vivax can stay dormant in the liver in the form of hypnozoites. This often leads to relapses of the disease, even weeks or months after the initial infection. This dormancy aspect complicates the treatment and eradication of P. vivax malaria, as it requires drugs that target both the blood stage of the parasite and the dormant liver stage.