Is a new pandemic possible? Conclusions of US scientists

American virologists studied coronaviruses related to MERS-CoV, but this is not a harbinger of a new pandemic

As reported by TUT.AZ, Doctor of Biological Sciences, Professor of the Department of Virology at the Faculty of Biology of Lomonosov Moscow State University Nikolai Nikitin, in a conversation with TASS, dispelled concerns about an impending pandemic of a new coronavirus.

"Statements about a new potential agent that will cause a pandemic are, to put it mildly, premature. The authors didn't discover America in the article. There are coronaviruses that could cause a new pandemic. But 'catching' the right one in advance is a very unlikely prospect," Nikitin emphasized in a conversation with TASS.

Earlier, some media outlets, citing a publication by American scientists in the journal Nature Communications, spread information about the discovery of a new coronavirus with pandemic potential. Rospotrebnadzor promptly refuted these reports, stating that it was only about research on already known viruses, and the epidemiological situation in Russia remains stable and under control.

"The authors of this fundamental work created an artificial system based on the spike protein of the Middle East Respiratory Syndrome coronavirus (MERS, caused by the MERS-CoV virus), and the main receptor necessary for binding to molecules on the cell surface was replaced with sequences from other coronaviruses. Unlike the coronavirus we are familiar with, MERS-CoV uses a different receptor to enter human cells. The main conclusion of this work is that some coronaviruses belonging to the same subgenus as MERS-CoV can use the same receptor as SARS-CoV-2 - angiotensin-converting enzyme type 2. However, we cannot say that these variants will cause a pandemic tomorrow," noted the virologist.

He especially emphasized that researchers experimented with artificially created "chimeric" proteins in laboratory conditions far from natural ones.

Infection from camels

MERS-CoV caused an outbreak of coronavirus infection in Saudi Arabia in 2012. It was transmitted to humans from dromedary camels and had a high mortality rate (about 35%), the scientist recalled. The causative agent of this infection still circulates in the world and periodically appears in camel farm workers.

"Now the mortality rate from infection is approaching zero thanks to emergency response measures. Fundamental research in this area is very important: it provides information about the evolution of viruses and, most interestingly, about the probabilities of them overcoming the interspecies barrier," the researcher explained.

The MSU professor recalled that over the past decades, thousands of coronaviruses from various animals have been discovered and studied, including bats, which serve as natural reservoirs for this virus.

"For a particular coronavirus to cause a pandemic, many factors need to coincide. Some viruses can enter human cells but cannot replicate in them due to a number of reasons, such as the work of the cellular immune system. Patient survival and the ability to transmit infection are also important issues. For example, with MERS and SARS, mass spread was unlikely, in part due to the poor adaptation of viruses to human cells and high mortality. Therefore, so far we only see works based on the study of molecular mechanisms of virus interaction with cells," he concluded.