The intestinal microbiota, i.e., the entirety of the microorganisms (bacteria, viruses, yeasts, etc.) present in the gut¹, plays an important role in human health as it mediates digestif, metabolic, neurological and immune functions. This normally carefully balanced ecosystem of microbes and interactions can however be knocked off-kilter by numerous factors, resulting in a state of dysbiosis able to aggravate numerous human pathologies.

A team from Institut Pasteur in Lille², in partnership with CEA-Jacob's IDMIT department, Inrae, and the Parisian Institut Pasteur and Saint Antoine Hospital, sought to determine the consequences of SARS-CoV-2 infection (the coronavirus responsible for COVID-19) on the intestinal microbiota. To reach its goals, the team performed analyses in a non-human primate model of COVID-19 disease developed by IDMIT. The researchers showed that SARS-CoV-2 infection does indeed cause intestinal dysbiosis comprising a significant modification of both the composition and function of the microbiota. Notably, they were able to demonstrate a correlation between the presence of SARS-CoV-2 in the upper airway and the modification of the relative abundance of certain bacterial species in the gut.

That dysbiosis furthermore continued after the elimination of the virus from the airways. Research is underway to determine if this dysbiosis affects the acute or post-disease phases of COVID-19. This work on an extra-pulmonary effect of COVID-19 deepens knowledge of the disease and may contribute to improving its treatment. 

1 -  The intestinal microbiota is primarily located in the small and large intestines, as the gastric acid keeps the stomach walls nearly sterile.

2 - Influenza, Immunity and Metabolism team headed by François Trottein, Center of Infection and Immunity of Lille, Institut Pasteur in Lille.