Footnotes

• Twitter @GiovanniCammar9, @gianluca1aniro

• Contributors QL and GI have written the initial draft of the manuscript. All authors have critically reviewed the manuscript and approved the final version for submission.

• Funding GC and GI would like to thank the Fondazione Roma for the invaluable support to their scientific research. This work was supported by the Ricerca Finalizzata Giovani Ricercatori 2018 of the Italian Ministry of Health (project GR-2018-12365734) to GI and by the BIOMIS grant of the Italian Ministry of Research to GC and GI. QL is supported by InnoHK, The Government of Hong Kong, Special Administrative Region of the People’s Republic of China.

• Disclaimer The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.

• Competing interests GC has received personal fees for acting as advisor for Ferring Therapeutics. GI has received personalfees for acting as speaker for Biocodex, Danone, Sofar, Malesci, Metagenics and Tillotts Pharma, and for acting as consultant/advisor for Ferring Therapeutics, Giuliani,Metagenics and Tillotts Pharma. QL is a named inventor of patent applications held by MagIC that is related to the treatment of bacterial infection with FMT.

• Provenance and peer review Commissioned; externally peer reviewed.