Immunotherapeutic Applications of Probiotics in Infectious Diseases Management: A Scoping Review

Probiotics are emerging as promising alternative therapies with diverse health applications, particularly in enhancing immunity and combating infectious diseases. This scoping review synthesizes evidence on the immunomodulatory and antimicrobial effects of well‐characterized strains, particularly species of Bifidobacterium and Lactobacillus . Probiotics contribute to gut health by strengthening intestinal barrier integrity, modulating immune responses, and producing antitoxins. They also demonstrate antiviral, antibacterial, and antifungal activity across experimental and clinical studies, with documented benefits in acute infectious diarrhea, respiratory tract infections, urinary tract infections, and selected fungal and bacterial diseases. Probiotics can be categorized into wild‐type and recombinant strains. While conventional wild‐type probiotics offer health benefits, they are limited by strain‐dependent efficacy, variable stress tolerance, and uncertain dosing requirements. In contrast, recombinant probiotics engineered through genetic modification are designed to improve stability, antimicrobial peptide production, toxin neutralization, colonization resistance, and vaccine‐delivery potential. Despite these advantages, the clinical use of recombinant probiotics necessitates careful consideration of safety concerns. These include immune dysregulation, mutagenesis, adverse metabolic effects, horizontal gene transfer, and excessive immune activation. Overall, substantial gaps remain regarding optimal dosing, timing of administration, long‐term safety, and comparative effectiveness across strains. Future research should integrate mechanistic studies with well‐designed clinical trials to define when and how probiotics—whether conventional or recombinant—can be safely incorporated into infectious disease management.