The Sars-Cov-2 pandemic has shown that Covid-19 can move from the respiratory system, most vulnerable to the infection, and affect other organs and systems in the body. There is mounting evidence suggesting that the GI tract is involved in this disease. Hence the idea from the Chinese group coordinated by Dr. Yeoh to evaluate possible damage to the GI tract, with particular attention to the intestinal microbiome, to better understand how best to restore its balance once the organism survives the infection.

The study, recently published in Gut, characterised the gut microbiota and immune response in 100 patients with COVID-19 during hospitalisation, 27 of which were followed up for up to 30 days after the negativization. The examination of the gut microbiota composition, by shotgun sequencing total DNA extracted from stools, showed that Sars-Cov-2 changed the composition of commensal bacteria, and in particular the concentration of bifidobacteria which were underrepresented in patients and remained low in stool samples collected up to 30 days after disease resolution. In addition to that, the alteration of some blood markers (such as C reactive protein, LDH, GOT and gammaGT) also concurred with a worsening of viral disease symptoms, confirming the importance of a balanced intestinal flora in supporting an optimal host immune response, especially in case of Sars-Cov-2 infection.

These data are coherent and confirm the results observed by Ceccarelli et al. (Frontiers in Nutrition, 2021) following a retrospective study including 88 hospitalized Covid-19 ICU patients with severe pneumonia. In this trial patients were administered a mixture of high concentration probiotics (Sivomixx^®800) in addition to the existing therapy showing a significant reduction in mortality rate compared to the 120 patients in the control group.