Helicobacter pylori: Commensal, symbiont or pathogen?

World J Gastroenterol. 2021 Feb 21;27(7):545-560. doi: 10.3748/wjg.v27.i7.545.


This review considers the data on Helicobacter pylori (H. pylori), which have been accumulated over 40 years since its description as an etiological factor in gastrointestinal diseases. The majority of modern publications are devoted to the study of the pathogenic properties of the microorganism in the development of chronic gastritis, peptic ulcer disease, and gastric cancer, as well as methods for its eradication. However, in recent years, there have been more and more studies which have suggested that H. pylori has a beneficial, or potentially positive, effect on the human body. The authors have attempted to objectively analyze the information accumulated in the literature on H. pylori. Some studies consider it as one of the recently identified human bacterial pathogens, and special attention is paid to the evidence suggesting that it is probably part of the composition of the human microbiome as a commensal (commensal from French to English is a table companion) or even a symbiont. The presented data discussing the presence or absence of the effect of H. pylori on human health suggest that there is an apparent ambiguity of the problem. The re-assessment of the data available on H. pylori infection is important in order to answer the question of whether it is necessary to create a program of mass H. pylori eradication or to apply a more personalized approach to treating patients with H. pylori-associated gastrointestinal diseases and to perform eradication therapy.

Keywords: Asthma; Commensal; Gastric cancer; Helicobacter pylori; Inflammatory bowel diseases; Microbiome; Pathogen; Peptic ulcer.

Publication types

  • Review

MeSH terms

  • Anti-Bacterial Agents / therapeutic use
  • Gastritis, Atrophic* / drug therapy
  • Helicobacter Infections* / diagnosis
  • Helicobacter Infections* / drug therapy
  • Helicobacter pylori*
  • Humans
  • Peptic Ulcer* / drug therapy
  • Stomach Neoplasms* / drug therapy


  • Anti-Bacterial Agents