Fecal Microbiota Transplantation Against Norovirus Infection: From Mechanisms to Clinical Evidence

Norovirus (NoV) is a leading global cause of acute gastroenteritis. Infected individuals shed virus at high concentrations in feces, and an extremely low infectious dose enables secondary transmission among household contacts, thereby expanding the scope of spread. Currently, no approved specific antiviral therapies for NoV infection are available; therefore, it is urgent to develop novel therapeutic strategies. Fecal microbiota transplantation (FMT) restores intestinal microbiota homeostasis by transplanting fecal microbiota from healthy donors, with well-proven efficacy in recurrent Clostridioides difficile infection. This narrative review summarizes the biological characteristics and infection mechanisms of NoV, the bidirectional interplay between intestinal microbiota and NoV, and the clinical evidence supporting FMT application in NoV infection. This review also discusses the potential therapeutic mechanisms of FMT in NoV infection, including microbiota engraftment and structural remodeling, repair of the intestinal mucosal barrier, and immune modulation, and highlights key considerations for its clinical application, such as donor screening, fecal preparation and delivery routes. Existing evidence suggests that FMT may present favorable efficacy and safety in the management of NoV infection, particularly in immunocompromised patients. Nevertheless, current studies are limited to case reports and small case series, lacking large-scale randomized controlled trials. Further high-quality studies and standardized protocols are required to validate the clinical value of FMT and facilitate its clinical translation for the management of NoV infection.