Parasites and Microbiota: Dual Interactions and Therapeutic Perspectives.

The human gut hosts a diverse and active community of bacteria that symbiotically support the physiology, metabolism, and immunity of the intestinal lining. Nevertheless, a dynamic community of parasites (helminths and protozoa) may share a habitat with gut-dwelling microbiota. Both microbiota and parasites can significantly change the physical and immunological environment of the gut, thus generating several mechanisms of interaction. Studying this field is crucial for understanding the pathogenesis of parasitic diseases. Additionally, intestinal microbiota and gut-dwelling parasites may interact with each other and with the host immunity to alleviate or exacerbate the disease. These interactions can alter the pathogenicity of both parasites and microbiota, thereby changing the infection outcomes and the overall disease profile. Parasites and microbiota interactions occur via several mechanisms, including physical alteration in both the gastrointestinal microenvironment and the adaptive and innate immune responses. By modulating the microbiota, treating parasitic infections and microbiota dysbiosis may be improved through knowing the mechanisms and consequences of the interactions between intestinal parasites and the microbiota. Thus, new biological tools of treatment including probiotics can be introduced, particularly with the emergence of drug resistance and adverse effects.