Intestinal Microflora Vs Protozoan Parasites: From Interaction to Competition

Aims: To reveal the interaction between intestinal microflora and the protozoan parasite organisms and how it affect their host’s performance. Discussion: The vertebrate gastro-intestinal system contain wide array of diverse but dynamic bacterial microbiota population that has ubiquitous consequences on its host’s well-being including physiology, nutrition, metabolism, and immunity, locally and systematically. Naturally, these bacteria share their milleu with a more or less similar population of parasitic eukaryotes (e.g., protozoan, helminths, and fungi). Both eukaryotes parasites in combination with the prokaryotic microorganisms as inhabitant normal microflora can dynamically shift the bio-physics and immune milleu of the intestine (locally) or even can affect its host as a whole (systematically), creating abundant chances for them to interact to each other; where ideally, both side is in equilibrium state. Beside their function, intestinal normal (commensal) microflora mainly contribute in several activities that control parasite survival and determines the outcome of several, if not many, parasite-base disease. Normal microflora actively limiting the pathogenicity of many parasites. The steadiness among the number and composition of normal microflora and its host seems vital to the host’s well-being perpetuation. But unfortunately, this interaction can further shifted into competition that can leads to the dominance of one party in number and probably also strength. Those spectrum of interactions may critically modify infection outcomes (active or dormant/carrier) and in turn affect the overall host condition. Active protozoan invasion may modify interaction between hosts and their normal resident microflora, either supporting or preventing against the condition of dysbiosis and inflammatory disease. Conversely, the microbiota controls parasite's settlement, multiplication, and even virulency; the properties that can modulate the interaction along the parasitism-mutualism sphere. Conclusion: Intestinal microflora composition control the pathogenesis of the protozoan infections.