A number of parasitic diseases have been reported to be transmitted by blood transfusion, including malaria, leishmaniasis, Chagas' disease, babesiosis, toxoplasmosis and filariasis. Majority of blood banks do not screen donor blood samples for these potentially pathogenic parasites, this poses great risk to the recipients of blood, especially immunocompromised patients and those who need regular, frequent and multiple transfusions. Transfusion-transmitted parasitic infections depend on several factors; asymptomatic parasitemia individual qualifies as a blood donor, the ability of the parasite to survive on stored donated blood, and the infected blood is transfused in a sufficient dose to a susceptible patient.