Heterospecific associations, symbiosis, mutualism, commensalisms, and parasitism; the host-parasite relationships; classification, morphology, life cycles, physiology, pathogenicity, diagnosis epidemiology, and control of protozoan parasites with emphasis on those of medical and veterinary importance in East Africa. Introduction to aquatic parasites, classification, life cycles, symptomatology. Concentration methods for protozoan cysts.