Relatives of pandemic virus found in labs in Cambodia and Japan

Bats are believed to be the original pandemic virus - Hugh Clark/Bat Conservation Trust/PA
Bats are believed to be the original pandemic virus - Hugh Clark/Bat Conservation Trust/PA
Coronavirus Article Bar with counter ..
Coronavirus Article Bar with counter ..

Scientists have discovered coronaviruses related to SARS-CoV-2, the virus responsible for the pandemic, have been stored for several years in laboratory freezers in Cambodia and Japan, supporting a theory that Covid-19 may not have originally emerged from China.

The viruses are the first known relatives of SARS-CoV-2 to be found outside of China, according to a report in science journal Nature.

The virus in Cambodia was found in Shamel’s horseshoe bats captured in 2010, while a team in Japan reported the discovery of another closely related coronavirus, found in frozen bat droppings dating back to 2013.

The most popular hypothesis about the origins about the pandemic that has killed 1.41 million globally is that SARS-CoV-2 spread into humans from an intermediate host, an animal species that picked it up and then helped it to jump between bats and humans.

The genome of the Cambodian virus has not yet been sequenced but if it is found to be closely related to, or an ancestor of the pandemic virus, it could provide crucial information about how SARS-CoV-2 was transmitted to people and inform the search for its origin, Veasna Duong, a virologist at the Pasteur Institute in Phnom Penh told Nature.

Coronavirus Live Tracker promo embed
Coronavirus Live Tracker promo embed

To provide these insights, the virus would have to share more than 97 per cent of its genome with SARS-CoV-2.

The Japanese virus was found in a local horseshoe bat called Rhinolophus cornutus but only shares 81 per cent of its genome with the pandemic strain.

Although this makes it too distant to reveal more about the origins of this year’s global health catastrophe, it does confirm that viruses closely related to SARS-CoV-2 are relatively common in Rhinolophus bats, and in bats found outside China, said Alice Latinne, an evolutionary biologist at the Wildlife Conservation Society Vietnam.

Some of the world’s leading experts on emerging diseases believe there is a strong possibility that Covid-19 did not initially emerge in Wuhan, China, the city that saw the first outbreak of the disease late last year. 

“It’s almost impossible to imagine this virus came from Wuhan,” Professor Wang Linfa, a renowned virus hunter and Singapore-based biologist, told the Telegraph earlier this month. “My theory is southern China or Southeast Asia,” he said.

Prof Wang has received funding from the World Health Organisation to search for the virus origin across Asia and beyond using a new method to screen animals and humans for prior infection to try to identify “intermediate hosts” that caused the virus to transmit from bats to humans.

“My test is going to be used as a frontline screening tool and so we are already going to do testing on samples from Southeast Asia, South America, the Middle East, Africa, United States,” he said.

The true origins of the deadly virus could lie in the trading of wildlife, much of it illegal, he said.

Protect yourself and your family by learning more about Global Health Security