EN
The human body is composed of 1014 cells, of which only 10% of them belong to the human host itself: the remaining 90% are microorganisms. Commensal microorganisms are necessary for the proper functioning of the human body and covers an area that could potentially become sites of adhesion of pathogenic microorganisms, it thus represents a form of competition for potential pathogens. The coexistence of fungi and bacteria in cases of systemic infections is a significant diagnostic and therapeutic problem, and the human immune system reacts differently, depending on the pathogen. Numerous publications exist concerning the relationship between microorganisms belonging to different ecological groups, the majority of which concern the interaction between macro-organisms and potential pathogens, or the synergistic relationship between parasitic species. However, there is still too little information concerning the role of natural microbiota in maintaining homeostasis and the relationships between particular species inhabiting the human organism.