Fecal Virome Transplantation in Human Disease and Livestock Production: Evidence, Mechanisms, and Translational Challenges

ABSTRACT

Fecal virome transplantation (FVT) is an emerging microbiome‐based intervention that transfers donor‐derived virus‐like particles, predominantly phages, while minimizing the transfer of viable donor bacteria. By modifying interactions between phages and their bacterial hosts, FVT may reshape recipient bacterial communities and thereby influence microbial metabolism and host immune responses. Current evidence supports the biological plausibility of this approach but does not yet demonstrate consistent therapeutic efficacy. Human studies remain few and heterogeneous, with mixed efficacy findings and insufficient evidence to establish long‐term safety. Preclinical studies suggest potential effects on metabolic, inflammatory and early‐life intestinal phenotypes, whereas evidence in livestock remains preliminary. Major knowledge gaps include inconsistent definitions and preparation methods, incomplete demonstration of viral sufficiency, uncertain engraftment and relationships between dose and response, compatibility between donors and recipients, and the potential transfer or mobilization of undesirable genetic material. This mini‐review summarizes the biological rationale and current evidence for FVT, evaluates methodological challenges and difficulties in establishing causality, and discusses the standardization and safety requirements needed to advance interventions based on the virome in human medicine and animal agriculture.