Patients with COVID-19 develop gut microbiota dysbiosis with depletion of Ruminococcus, Alistipes, Eubacterium, Bifidobacterium, Faecalibacterium, Roseburia, Fusicathenibacter, and Blautia, and enrichment of Eggerthella, Bacteroides, Actinomyces, Clostridium, Streptococcus, Rothia, and Collinsella. A dysregulated gut environment could increase the expression of ACE2 in the gut and favor more severe disease [14]. This evidence concerns the gene ACE2 and COVID-19.