Another coronavirus found in bats: the pandemic’s “close relative” and the key to the riddle

Scientists have discovered two viruses in frozen bats and their feces stored in laboratories in Cambodia and Japan, reports Nature News & Comment.

As SARS-CoV-2, the virus that causes COVID-19, continues to spread around the world, scientists have never stopped searching for the origin of the pathogen, writes livescience.com. Like the “cousin” of today’s virus, SARS-CoV, which caused outbreaks of severe acute respiratory syndrome (SARS) in the early 2000s, SARS-CoV-2 originated in horseshoe bats (of the genus Rhinolophus), But there is evidence that the virus may have penetrated another animal before infecting humans.

By looking for coronaviruses related to the current virus, scientists can help solve the mystery of how SARS-CoV-2 jumped from bats to humans and caused the current pandemic. Scientists have now discovered the virus in Cambodia, virologists say.

“It just came to our attention then. It was very interesting and at the same time very surprising,” says Dr. Veasna Duong, a virologist at the Pasteur Institute of Cambodia in Phnom Penh, who led the research. The research is ongoing and has yet to be published in any scientific journal.

The research team discovered the virus in two Shamel horned bats (R. shameli) that were captured in 2010 and have remained frozen ever since. To confirm the virus’s association with SARS-CoV-2, the researchers examined a small segment of the viral genome. This segment consists of 324 base pairs – RNA building blocks. The segment is very similar to known members of the coronavirus family, says Alice Latinne, an evolutionary biologist with the Vietnam Wildlife Society.
According to the researcher, this segment is often used to identify a new coronavirus among the coronaviruses that we already know.

And the team of researchers discovered that the short segment of the new virus is similar to SARS-CoV-2, as well as corresponding fragments of its closest known relative, the bat coronavirus called RaTG13. Scientists now have to isolate the entire genome of the newly discovered virus, which probably contains around 30,000 base pairs, to find out exactly how close it is to SARS-CoV-2.

So far, the team has targeted around 70 percent. viral genome, but critical genes have yet to be analyzed. Including those with instructions on how to create a spike protein that allows the virus to enter cells.

RaTG13 is the closest known relative of SARS-CoV-2 to date, with 96 percent of its genome overlapping with the pandemic virus. and probably separated from the common pathogenic ancestor 40-70 years ago.

Therefore, if the newly discovered virus is at least 97 percent. similar to SARS-CoV-2, it would be closer to a “relative” than RaTG13. If the sequences are at least 99 percent. A similar newly discovered virus could be the direct ancestor of the pandemic, says Aaron Irving, an infectious disease researcher at Zhejiang University in China.

There is another alternative: the newly discovered virus may not be as close to SARS-CoV-2 as RaTG13. For example, in the studio, on November 2. The scientific journal Emerging Infectious Diseases, published in 2006, reports that the coronavirus, recently found in frozen bat feces in Japan, overlaps SARS-CoV-2 by about 81 percent. A virus called Rc-o319 cannot enter human cells using the same receptor that SARS-CoV-2 uses.

Whether the virus found in Cambodia can infect human cells remains a mystery. In any case, detecting new coronaviruses in bats can provide clues as to how SARS-CoV-2 jumped on humans and help us predict future pandemics.

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