Introduction: The human gut microbiome consists of a complex community of trillions of microorganisms that perform essential functions in host immunity, metabolism, and barrier defense. Emerging evidence links disruptions in microbial balance—known as dysbiosis—with heightened vulnerability to infectious diseases. With technological advances in sequencing and metagenomics, our understanding of the gut microbiome’s role in infectious disease progression has deepened. This review investigates recent findings on the microbiome’s protective functions, its dysfunction in infection, and how therapeutic manipulation of gut microbes may alter disease outcomes.
Methods: This review analyzed scientific literature published between 2015 and 2025. Databases including PubMed, Google Scholar, ScienceDirect, and PMC were searched using terms like “gut microbiome,” “dysbiosis,” “infectious diseases,” “probiotics,” and “fecal microbiota transplantation (FMT).” From over 300 initial results, 10 peer-reviewed articles were selected based on relevance, scientific rigor, and clinical applicability. Data from selected studies were categorized into five main themes: dysbiosis and infection risk, immune modulation by gut microbiota, antibiotic effects, novel therapeutic approaches, and future research directions.
Results: Evidence consistently shows that gut microbiome composition plays a decisive role in host susceptibility to infection. Dysbiosis following antibiotic exposure often leads to reduced microbial diversity and the overgrowth of pathogens such as Clostridioides difficile (Lathakumari, 2024; McKenney et al., 2015). Commensal microbes are crucial for immune system calibration, as they enhance mucosal barrier integrity and stimulate regulatory T-cell responses via metabolites like short-chain fatty acids (SCFAs) (Maciel‑Fiuza et al., 2023). Interventions such as probiotics and FMT have demonstrated success in restoring gut flora and reducing infection recurrence, particularly in antibiotic-resistant cases (Seo et al., 2024; Davido et al., 2024). Nonetheless, individual variability in microbiota composition and treatment outcomes highlights the need for personalized approaches and regulatory guidelines.
Conclusion: The gut microbiome is a key player in preventing and modulating the course of infectious diseases. Strategies aimed at preserving or restoring microbial equilibrium—through dietary, microbial, or genetic interventions—can offer promising results in both prevention and therapy. To fully integrate microbiome science into clinical infectious disease management, more robust clinical trials, standardized treatment protocols, and personalized approaches are essential. The future of infection control may rely on our ability to manipulate these microbial ecosystems effectively.
Keywords: Gut microbiome, infectious diseases, dysbiosis, probiotics, fecal microbiota transplantation