Scientists discover a virus very similar to COVID-19 in bats in Laos

Scientists from the Pasteur Institute in Paris announced that they have discovered in bats from the north of Laos a virus strain very similar to that of the SARS-CoV-2 that caused COVID-19.

The conclusions of this research are available from this Wednesday on the scientific platform “Research Square”, in free access.

It is a study that has not yet been independently evaluated by other researchers, before being published in a scientific journal, as is usually the case.

The French researchers, together with their peers from the Pasteur Institute of Laos and the national university of that country, carried out between the end of 2020 and the beginning of 2021 a mission in the north of Laos to analyze different species of bats that live in calcareous caves.

“The initial idea was to try to identify the origin of this epidemic”, explained to AFP Marc Eloit, head of the laboratory specialized in the discovery of new pathogens at the Pasteur Institute in Paris.

After analysis of the various samples collected, and thanks to matching data, “We suspect that some insectivorous bats could harbor the virus.”

The samples were collected in a region that is part of an immense karst relief, with calcareous geological formations, ideal for harboring bat colonies, extending from Laos to northern Vietnam and southern China.

“Laos shares that common territory with southern China, full of caverns where bats live, so we decided to explore that side,” explains Marc Eloit. What happens in that area is representative of the entire cave ecosystem.

The sequences of the viruses found in bats are almost identical to those of SARS-CoV-2 (the scientific name for the covid-19 virus) and the researchers were able to show that it is capable of contaminating human cells.

However, the viruses tested lacked what is known as the “furin cleavage site,” a function present in SARS-CoV-2, which activates the Spike protein.

This protein is what allows the virus to improve its penetration power in human cells, and therefore, it is the key to the pathogenic power of the virus that has spread throughout the planet.

The mystery of the spread of the virus

Several hypotheses could explain this missing link in the viruses just analyzed, explains Marc Eloit.

“Perhaps a non-pathogenic virus first circulated among humans before mutating”, suggests this expert.

“Or perhaps a virus very close to the viruses identified has this cleavage site, and we haven’t found it yet.”

But the most sensitive question is another: “How is it possible that the bat virus found in the caves ended up in Wuhan?” a city that is 2,000 km further north.

Wuhan is the Chinese city and official origin of the covid-19 pandemic.

For now there is no clear answer to this question.

Be that as it may, this study “represents a great advance in identifying the origin of SARS-CoV-2,” estimates Eloit.

His main conclusion would be that there are viruses very close to SARS-CoV-2 in bats, capable of infecting man without an intermediary animal, such as the pangolin.

At the end of August, a group of experts commissioned by the World Health Organization (WHO) to report on the origin of COVID-19 warned that the investigations were at a “stalemate”.

The scientists who raised the alarm signal were part of the team of 17 researchers that the WHO sent to China, where they had to work alongside 17 other Chinese researchers.

That initial investigation, in January, led to a joint report on March 29, which did not provide a clear answer to the questions.