Abstract:Viral diseases pose great threats to human and animal health.In light of the limitations of vaccination and antiviral therapies available,developing safe,broad-spectrum,and inexpensive novel antivirals is an urgent task.Probiotics are viable microorganisms with a lot of benefits to the body.The antiviral effects and underlying mechanisms of probiotics are research hot spots at the moment.This review summarizes the multiple antiviral modes of probiotics,such as promoting the tight junction of intestinal cells and producing beneficial substances to maintain the mucosal barrier of the host,competing with viruses for targets or directly inhibiting and killing viruses,stimulating the immune system and regulating innate and adaptive immune response,or secreting antiviral metabolites to exert antiviral effects.The review is expected to provide insights into the development of probiotics-based antivirals.