Two lab freezers in Asia have yielded surprising discoveries. Researchers have told Nature they have found a coronavirus that is closely related to SARS-CoV-2, the virus responsible for the pandemic, in horseshoe bats stored in a freezer in Cambodia. Meanwhile, a team in Japan has reported the discovery of another closely related coronavirus — also found in frozen bat droppings.

The viruses are the first known relatives of SARS-CoV-2 to be found outside China, which supports the World Health Organization’s search across Asia for the pandemic’s animal origin. Strong evidence suggests that SARS-CoV-2 originated in horseshoe bats, but whether it passed directly from bats to people, or through an intermediate host, remains a mystery.

https://www.nature.com/articles/d41586-020-03217-0

The virus in Cambodia was found in two Shamel’s horseshoe bats (Rhinolophus shameli) captured in the country’s north in 2010. The virus’s genome has not yet been fully sequenced — nor its discovery published — making its full significance to the pandemic hard to ascertain.

That is the case with the other virus, called Rc-o319, identified in a little Japanese horseshoe bat (Rhinolophus cornutus) captured in 2013. That virus shares 81% of its genome with SARS-CoV-2, according to a paper1 published on 2 November — which makes it too distant to provide insights into the pandemic’s origin, says Edward Holmes, a virologist at the University of Sydney in Australia.

No matter what the Cambodian team finds, both discoveries are exciting because they confirm that viruses closely related to SARS-CoV-2 are relatively common in Rhinolophus bats, and even in bats found outside China, says Alice Latinne, an evolutionary biologist at the Wildlife Conservation Society Vietnam in Hanoi, who has seen some of the Cambodian team’s analysis but was not involved in the investigation.

“This is what we were looking for, and we found it,” says Duong. “It was exciting and surprising at the same time.”