The bacteria that lurks in the intestines of patients with COVID-19 may play a role in how they get sick with the disease, according to new research.
Although coronavirus is primarily a respiratory disease, there is growing evidence to suggest that the gastrointestinal tract is involved, said scientists at the Chinese University in Hong Kong.
The team studied samples from 100 patients treated at two Hong Kong hospitals to see how the so-called microbiome in the digestive system can affect the recovery from the deadly virus.
“The composition of the intestinal microbiome has been significantly altered in patients with COVID-19 compared to non-COVID-19 individuals, regardless of whether the patients received medication,” they wrote in the British Medical Journal’s Gut publication.
“Based on several patients surveyed in this study for up to 30 days after the elimination of SARS-CoV-2, the intestinal microbiota is likely to remain significantly altered after recovery from COVID-19,” they said.
The researchers said that patients with severe disease have elevated levels of inflammatory cytokines and inflammatory markers in the blood plasma – and that there is “substantial involvement” of the gastrointestinal tract during infection, given the “altered composition of the intestinal microbiota in individuals infected with SARS-CoV. -two”.
Cytokines, which are molecules that allow cells to communicate, play a crucial role in healthy immune function. Many cytokines, however, can result in what is known as a “cytokine storm”.
“These results suggest that the composition of the intestinal microbiota is associated with the magnitude of the immune response to COVID-19 and subsequent tissue damage and, therefore, may play a role in regulating the severity of the disease,” they wrote.
The scientists also found that because a small subset of patients had dysbiosis of the intestinal microbiota, or imbalance, even 30 days after recovery, this could be a potential explanation for the persistence of some symptoms in what is known as long COVID.