The gut microbiome appears to be altered in patients with COVID-19, finds a study in Gut. Researchers compared blood and stool samples of roughly 100 patients with COVID-19 in Hong Kong with samples from other people taken before the pandemic. Nearly half the COVID-19 patients had mild disease.
Several bacteria species were associated with disease severity after adjustment for antibiotic use. For instance, compared with controls, patients with COVID-19 had smaller populations of Faecalibacterium prausnitzii and Eubacterium rectale, which have known immunomodulatory potential. Even among those who had recovered from COVID-19, the gut remained distinct from non-COVID patients a median of 6 days after testing negative.
The authors say that their results "suggest that gut microbiota composition is associated with the magnitude of the immune response to COVID-19 and subsequent tissue damage and thus could play a role in regulating disease severity." They add, "Bolstering of beneficial gut species depleted in COVID-19 could serve as a novel avenue to mitigate severe disease, underscoring the importance of managing patients' gut microbiota during and after COVID-19."