The COVID19 pandemic is spreading to every corner of the world, but not everyone is falling sick at the same rate. A new study published on the preprint server medRxiv in April 2020 suggests that the composition of the gut microbiome could partially explain the difference in susceptibility. This adds a new dimension to what is currently known about the disease.

Clinicians have observed that more than 60% of patients with COVID19 have diarrhea, nausea, and vomiting, and these symptoms predict a worse outcome overall. Severe acute respiratory syndrome coronavirus 2 (SARSCoV2), the causative agent of COVID19 disease, enters the human host cell by binding to the angiotensinconverting enzyme (ACE) 2, which acts as the viral receptor. This molecule is found at higher concentrations in the ileum and colon and regulates intestinal inflammation. ACE2 directly affects the gut microbiome, and indirectly the cardiopulmonary risk.

Older and sicker individuals are more likely to fall sick when exposed to this virus. The current study investigates the potential link between the gut microbiome and the clinical course and features of COVID19. The researchers selected a set of proteins that could act as biomarkers to forecast the progression to severe disease. However, they also examined whether these proteins could help understand what makes a person more or less susceptible to the disease, and what role the gut microbiota plays in regulating the levels of these biomarkers in healthy people.

The researchers also discovered that fecal metabolic analysis may have possible amino acid-related pathways linking the intestinal microbiota to inflammation. This study suggests that intestinal microbiota may be the basis for the predisposition of normal individuals to severe COVID19.

Read more: Medrxiv