The high concentration of a particular intestinal bacteria that represses the coronavirus’s binding towards human cells receptors is found to have played a crucial part in the low COVID-19 death rate seen throughout Asia and Northern Europe, according to an investigation led by an academic team at Nagoya University.
Scientists worldwide have suggested that there could be an additional factor that helped Asia and Nothern European Countries achieve low mortality rates due to COVID. Genetic and immunological differences and the administration of the BCG vaccine during the first year of life to guard against tuberculosis are frequently suggested as reasons. So from the result of research from Kyoto Prefectural University, other dietary reasons such as consumption of green tea called catechins help suppress the activity of the virus inside the body.
The highly contagious omicron variant has been found to result in less severe infections than those of the delta, and mortality rates have been reduced to be like the rate of influenza.
However, the mortality rate for COVID-19 increases as you get older. Other risk factors are smoking, diabetes, obesity, and a history of respiratory infections; however, COVID-19 vaccination reduces the risk of severe disease and death.
To understand the mystery behind the low mortality rate in some regions, Nagoya University scientists analyzed the raw sequencing of gut micro-organisms from healthy subjects from 10 countries from an open database.
The researchers used a complex machine learning technique almost a year ago to research the connection between intestinal bacteria and death rates. The team studied 30 crucial intestinal bacteria and discovered that the lowest concentration of one known as collinsella was the most significant predictor that explained the high mortality rate of COVID-19 and had a critical statistical significance.
The scientists classified the data into five kinds of gut-based bacteriological ecosystems known as enterotypes, based on the compositional similarities in their micro-organisms. They compared these with the mortality rates of 10 countries and discovered that the collinsella level was not positively correlated with mortality rates.
When COVID-19 mortality rates were low, as the cases in South Korea, Japan, and Finland where the enterotype with the highest concentration of collinsella was the most dominant with 34 percent to 61 percent in totality, according to the study, Belgium, Britain, Italy, and the U.S., where mortality rates were high, enterotypes having the two with the lowest levels of collinsella dominated while only 4 or 18% the subjects had the type with the highest level. Other countries studied were Canada, Germany, and Mexico.
“I’m not saying that intestinal bacteria alone can cure COVID-19,” stated the study’s principal researcher, Masaaki Hirayama, an associate professor at the university’s Graduate School of Medicine. “The purpose of this study was to see if we could make a breakthrough in treatment if we could find at least one thing related to that factor.”
Hirayama claimed the collinsella alters the gut’s acid bile to the acid ursodeoxycholic, which is known to inhibit the binding of coronavirus with its receptor and reduce the risk of a deadly immune response known as a Cytokine Storm.
The study was given an exhaustive peer-review process before being published by the U.S. open-access medical and science journal Plos One in late November. Many factors, including stress and age, may affect the gut micro-organisms. However, enterotypes are believed to be affected by the intake of certain foods and are not significantly influenced by gender or race, Nagoya University researchers said.
Hirayama says it’s not yet clear whether the mortality rate is higher in vaccinated and those with lower levels of collinsella. Based on the results from the research, he’s started work on a collaboration with respiratory medicine specialists to discover if the chemicals created by these intestinal bacteria play a part in determining whether certain patients get gravely ill and others don’t.
“Serious cases of the disease have rapidly declined due to vaccination, so I don’t think we need to worry too much about low collinsella levels in some Japanese people,” he added. “Most Japanese and other Asians have high levels of bifidobacteria and collinsella.”