Thread by @Ayjchan

People keep messaging me with this @NatureNews article about SARS-CoV-2-related viruses discovered in Japan and Cambodia.

What does this mean in regards to the search for the #originsofSARSCoV2 ? nature.com/articles/d4158…

First, kudos to the article: "Strong evidence suggests that SARS-CoV-2 originated in horseshoe bats, but whether it passed directly from bats.. or.. an intermediate host, remains a mystery."

Scientific consensus is that bats are the ultimate source. But how did it get to Wuhan?

The Cambodian virus from 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."

Researchers told the reporter that in order to be more useful to the search for the pandemic origin, the Cambodian virus would need to share >97% of its genome with SARS-CoV-2.

BECAUSE the closest relative to SARS2 is RaTG13 batCoV collected by the WIV in 2013 from Yunnan China.

Similarly, the Japanese horseshoe bat virus Rc-o319 only shares 81% genome identity with SARS-CoV-2 "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."

"The new virus would have to be at least 99% similar to SARS-CoV-2 to be an immediate ancestor of the current pandemic virus, says Irving (Aaron Irving, an infectious-diseases researcher at Zhejiang University in Hangzhou, China)."

People. I'm literally copying and pasting from the article. But I see members of the public going around saying that a 97% identical virus to SARS2 has been found in Cambodia or Japan.

This is making me feel like a good number of people don't read articles before sharing.

I'd also like to take this opportunity to raise an important point about global virus sampling efforts and anticipated outcomes. This article is talking a bat virus sample collected a decade ago in Cambodia - finally getting sequenced and being identified as a SARS-like virus...

Can we re-evaluate how global virus sampling is conducted around the world? How quickly these samples are processed, sequenced, shared publicly (or at least internationally on a restricted database)?
RaTG13 - 7 years, released post-covid
Cambodian virus - 10 years, post-covid

Is the current workflow truly expected to produce vaccines or therapeutics that will prepare us against future pandemics?

Seeing as how we are entering "an era of pandemics"? theguardian.com/commentisfree/…

At the very least, if all natural pathogen sequences were shared on an internationally-hosted database, this would greatly expedite the ability to trace virus origins and whether lab activities (including sample collection from animals or remote human pops) pose outbreak risks.

I know @K_G_Andersen and I disagree on this point: Whether spillover from virus sampling counts as natural origins (Kristian's opinion) or lab-based scenario (imo). But I hope we can agree that identifying the activity that led to spillover is important to reducing risk.