MODERN ASSESSMENT OF THE EFFECT OF INTESTINAL PROTOZOAL INFECTIONS ON GUT MICROBIOTA COMPOSITION AND LOCAL IMMUNITY

Intestinal protozoal infections remain an important cause of gastrointestinal morbidity, particularly in children and populations exposed to unsafe water, inadequate sanitation, and repeated enteric infections. Beyond direct epithelial injury, protozoa such as Giardia duodenalis, Cryptosporidium spp., Entamoeba histolytica and Blastocystis spp. interact dynamically with the resident gut microbiota and mucosal immune system. These interactions may alter microbial diversity, bacterial biofilm structure, epithelial barrier integrity, secretory immunoglobulin A production, cytokine signaling, and the balance between inflammatory and regulatory immune responses. Modern assessment therefore requires a combined approach that integrates parasitological testing with molecular microbiome analysis and markers of local immunity. The present thesis summarizes current concepts on protozoa-microbiota-immune interactions and outlines contemporary diagnostic approaches relevant to clinical and research practice.