The bacteria lurking in COVID-19 patients’ intestines may play a role in how sick they get from the illness, according to new research.
Although the coronavirus is primarily a respiratory disease, there is increasing evidence that suggests the GI tract is involved, scientists at the Chinese University of Hong Kong said.
The team studied samples from 100 patients treated at two Hong Kong hospitals to see how the so-called microbiome in the digestive system might affect recovery from the deadly bug.
“Gut microbiome composition was significantly altered in patients with COVID-19 compared with non-COVID-19 individuals irrespective of whether patients had received medication,” they wrote in the British Medical Journal’s publication Gut.
“Based on several patients surveyed in this study for up to 30 days after clearing SARS-CoV-2, the gut microbiota is likely to remain significantly altered after recovery from COVID-19,” they said.
The researchers said patients with severe illness exhibit high blood plasma levels of inflammatory cytokines and inflammatory markers — and that there is “substantial involvement” of the GI tract during infection, given “altered gut microbiota composition in SARS-CoV-2 infected subjects.”
Cytokines, which are molecules that allow your cells to talk to each other, play a crucial role for healthy immune function. Too many cytokines, however, can result in what’s known as a “cytokine storm.”
“These results suggest that gut microbiota composition is associated with the magnitude of immune response to COVID-19 and subsequent tissue damage and thus could play a role in regulating disease severity,” they wrote.
The scientists also found that because a small subset of patients showed gut microbiota dysbiosis, or imbalance, even 30 days after recovery, this could be a potential explanation for why some symptoms persist in what is known as long COVID.