Acute infection disrupts the healthy balance between good and bad microbes in the gut

In delving into the effects of the virus that causes COVID-19 on a patient's microbiome, a collection of microbes that live inside and on the surface of the human body, scientists at Rutgers University have found that acute infection disrupts the healthy balance between good and bad microbes in the gut, especially when
treated with antibiotics.

The scientists say this work could lead to the development of probiotic supplements to correct any intestinal imbalances
in future patients.

In the scientific journal Molecular Biomedicine, the researchers describe the first results of an ongoing study examining the microbiomes
of patients and volunteers at Robert Wood Johnson University Hospital in New Brunswick.
The study began in May 2020, early in the pandemic, to study the microbiome, as many COVID-19 patients complain of gastrointestinal problems – both during the acute phase of the disease and during recovery
.

Martin Blaser, the Henry Rutgers Chair in the Human Microbiome at Rutgers, director of the Center for Advanced Biotechnology and Medicine (CABM) at Rutgers and one of the study's authors, said: "We wanted to gain a deeper understanding by looking at samples, which will give us an indication
of the state of the human gut microbiome.
" "We found that although there was a difference between people with COVID-19 and people who didn't have the disease, people who took antibiotics had the greatest
difference from others.
"

It was a common practice
to treat COVID-19 patients with a round of antibiotics early in the pandemic, before the introduction of vaccines and other antivirals, in an attempt to target possible secondary infections, Blaser said.
Blaser is also a professor of medicine, pathology, and laboratory medicine at Rutgers University's Robert Wood Johnson School of
Medicine.

Blaser said humans carry a large variety of microorganisms
.
These microorganisms live in the gastrointestinal tract, skin, and other organs, and are most
abundant in the colon.
Scientists such as Blaser have shown in recent decades that the microbiome plays a key role in human health, interacting
with metabolism, the immune system and the central nervous system.

The microbiome has many different functions
.
"One is to protect the human body from pathogens, be it bacteria, viruses or fungi
," Blaser said.
"This goes deep into evolution, maybe 1 billion years of evolution
.
"

Medical problems often arise when the balance between beneficial and pathogenic microbes in a person's microbiome is upset, a condition known as dysbiosis
.

The scientists studied the microbiome
by measuring the number of microbes in stool samples from 60 subjects.
The study group consisted of
20 COVID-19 patients, 20 healthy donors, and 20 COVID-19 recovery subjects.
They found significant differences
in populations of 55 different bacteria when comparing the microbial communities of infected patients with those of healthy and recovered patients.

Rutgers scientists plan to continue testing and tracking patients' microbiomes in the study to determine the long-term effects of
COVID-19 on individual microbiomes.

"Further investigation of patients will improve understanding
of the role of the gut microbiota in COVID-19 disease progression and recovery," Blaser said.
"These findings may help identify microbial targets and probiotic supplements to improve the treatment
of COVID-19.
"