Research from Rutgers University shows that acute infection with COVID-19 leads to disruptions in the gut microbiome, which may at least partly explain gastrointestinal issues experienced by many patients during the acute and recovery phases of infection.
These microbial imbalances were worsened by treatment with antibiotics, which were given to many COVID-19 patients earlier in the pandemic to try and stop secondary bacterial infections.
As reported in the journal Molecular Biomedicine, the researchers carried out 16S rRNA sequencing of stool samples from 20 COVID-19 positive patients, 20 people who had recovered from COVID-19 and 20 healthy controls.
“We wanted to gain a deeper understanding by looking at specimens that would give us an indication about the state of the gut microbiome in people,” said Martin Blaser, a professor at Rutgers University, and co-senior author on the study in a press statement.
The results showed significant differences in microbiome composition in COVID-19 patients compared with the group of recovered people and healthy controls. For example, Bacteroidaceae and Ruminococcaceae species of bacteria were present at lower numbers in COVID-19 patients compared with the other two groups.
“In contrast, Prevotellaceae increased in abundance with acute COVID-19 infection which reached the highest levels post-recovery, a trend particularly apparent in subjects without antibiotic use,” note the authors.
Of the three groups, 10% of the control, 60% of the COVID-19 positive, and 20% of the recovered individuals had taken antibiotics during the previous 6 months. The research team found these individuals had more severe gut dysbiosis than those who did not take antibiotics in the same group.
“What we found was that, while there were differences between people who had COVID-19 and those who were not ill, the biggest difference from others was seen in those who had been administered antibiotics,” emphasized Blaser.
This was a relatively small and observational study, but the researchers now want to try and confirm their findings and also carry out follow-up testing on the participants of this study to see how their microbiomes change over time.
“Further investigation of patients across the severity gradient in expanded longitudinal cohorts will enhance understanding of the role of the gut microbiome in COVID-19 disease progression and recovery,” conclude the authors. “These findings may help identify microbial targets and probiotic supplements for improving COVID-19 treatment.”