COVID-19 Infection Impacts Gut Microflora

Humans carry numerous populations of microbes, with each year detailing more research surrounding how these microbes play a pivotal role in human health. Researchers from Rutgers University decided to investigate how gut microflora reacts to illness from COVID-19, specifically the ratios of bad and good bacteria left after recovery. Their work, published in the journal Molecular Biomedicine, describes the results of microbiomes from patients and volunteers at Robert Wood Johnson University Hospital in New Brunswick.

Microbiomes play many different functions in the body. "One is to protect the human body against invading pathogens, whether they're bacteria or viruses or fungi," says senior author Martin Blaser, director of the Center for Advanced Biotechnology and Medicine (CABM) at Rutgers. 

The work for this study began back in May 2020, the early stages of the pandemic. The team wanted to further understand why individuals suffering from infection with SARS-CoV-2 complained of gastrointestinal issues during both acute phases of illness and while recuperating.

"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," says Blaser, who also holds the Henry Rutgers Chair of the Human Microbiome at Rutgers University. "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."

Blaser recalls how, before vaccines were available, physicians often utilized antibiotics in an attempt to target possible secondary infections. Since humans contain such a diverse and wide array of microflora, with the most extensive population in the colon, it's not surprising to imagine that some alterations resulted from antibiotic administration. When the balance between harmful and beneficial bacteria becomes drastic, it can lead to a condition known as dysbiosis and impact overall metabolism, immunity, and more.

In total, the team measured populations of microorganisms in stool samples from 60 subjects comprised of 20 COVID-19 patients, 20 healthy donors, and 20 subjects recovered from COVID-19. They found significant differences in the population numbers of 55 different species of bacteria when comparing the microbiomes of infected patients versus the healthy and recovered patients.

For the future, the Rutgers researchers plan to test and track the microbiomes of additional patients to uncover more about the long-term impacts on individual microbiomes from COVID-19. "Further investigation of patients will enhance understanding of the role of the gut microbiome in COVID-19 disease progression and recovery," says Blaser. "These findings may help identify microbial targets and probiotic supplements for improving COVID-19 treatment."