Saturday, March 27, 2021

Coronavirus: "Lab Leak: A Scientific Debate Mired in Politics — and Unresolved"

Let me say upfront, I have no special insight into the arguments, pro and con. I have enough science knowledge to follow the broad outlines of the story but going deeper I have to move slowly with just a filmy, almost ethereal matrix to hang it all on. 
What I know more substantively is that any questioning is met with attempts at the politics of personal destruction, which is an interesting reaction.

From UnDark:

More than a year into the SARS-CoV-2 pandemic, some scientists say the possibility of a lab leak never got a fair look.

Nikolai Petrovsky was scrolling through social media after a day on the ski slopes when reports describing a mysterious cluster of pneumonia cases in Wuhan, China caught his eye. It was early January 2020, and Petrovsky, an immunologist, was at his vacation getaway in Keystone, Colorado, which is where he goes most years with his family to flee the searingly hot summers at home in South Australia. He was soon struck by an odd discrepancy in how the pneumonia cases were portrayed. Chinese authorities and the World Health Organization were saying there was nothing to worry about, but locals in the area, he says, were posting about “bodies being stretchered out of houses in Wuhan and police bolting apartment doors shut.”  

Petrovksy is a professor at Flinders University, near Adelaide, and he is also founder and chairman of a company called Vaxine that develops immunizations for infectious diseases, among other projects. Since 2005, he’s received tens of millions of dollars in funding from the U.S. National Institutes of Health to support the development of vaccines and compounds called adjuvants that boost their effects. After Chinese scientists posted a draft genome of the novel coronavirus SARS-CoV-2, the disease culprit in Wuhan, Petrovksy — who by this time had put skiing on the backburner to work from his Colorado home office — directed his colleagues down under to run computer modeling studies of the viral sequence, a first step towards designing a vaccine.

This generated a startling result: The spike proteins studding SARS-CoV-2 bound more tightly to their human cell receptor, a protein called ACE2, than target receptors on any other species evaluated. In other words, SARS-CoV-2 was surprisingly well adapted to its human prey, which is unusual for a newly emerging pathogen. “Holy shit, that’s really weird,’” Petrovsky recalls thinking.

As Petrovsky considered whether SARS-CoV-2 may have emerged in lab cultures with human cells, or cells engineered to express the human ACE2 protein, a letter penned by 27 scientists appeared suddenly on Feb. 19 in the prestigious medical journal The Lancet. The authors insisted that SARS-CoV-2 had a natural origin, and they condemned any alternate hypotheses as conspiracy theories that create only “fear, rumors, and prejudice.”

Petrovksy says he found the letter infuriating. Conspiracy theorists is “the last thing we were, and it looked to be pointing at people like us,” he says.

Last month, a team of international scientists completed a month-long visit to Wuhan to investigate SARS-CoV-2’s origins. Convened by the WHO, and closely monitored by Chinese authorities, the team concluded initially that a lab leak was so unlikely that further investigations of it were unnecessary. The WHO’s director general later walked that statement back, claiming that “all hypotheses remain open and require further analysis and studies.” A group of 26 scientists, social scientists, and science communicators — Petrovksy among them — have now signed their own letter arguing that WHO investigators lacked “the mandate, the independence, or the necessary accesses” to determine whether or not SARS-CoV-2 could have been the result of a laboratory incident.

The WHO investigation follows a year during which debates over SARS-CoV-2’s origins turned increasingly acrimonious. Chinese officials were, and still are, unwilling to provide information that might settle lingering questions about where the virus came from, and in the absence of critical data, expert views coalesced around two competing scenarios: One that a lab leak was plausible and needed more scrutiny, and another that SARS-CoV-2 had almost certainly spilled over from nature and that the odds of a lab leak were so remote that the possibility could essentially be taken off the table. Those insisting on a natural origin say the virus lacks genetic features that would show it to have been deliberately engineered. But it’s also possible that SARS-CoV-2 evolved naturally in the wild before it was brought into a lab to be studied, only to subsequently escape. The Wuhan Institute of Virology, which many see as the likeliest site of a breakout, houses one of the largest collections of coronaviruses in the world.

David Relman, a microbiologist at Stanford University, says a lab leak was never the subject of a “fair and dispassionate discussion of the facts as we know them.” Instead, tempers soon began to flare as those calling for a closer look at possible lab origins were dismissed as conspiracy theorists spouting misinformation. Election-year politics and growing Sinophobic sentiments only added to the tensions. Attacks on Asian Americans had been escalating since the pandemic began, and with then-President Trump fuming about a “Chinese virus,” many scientists and reporters became “cautious about saying anything that might justify the rhetoric of his administration,” says Jamie Metzl, a senior fellow at the Washington, D.C.-based Atlantic Council, an international affairs think tank.

It could have been career suicide for scientists to voice suspicions about a possible lab leak, says Metzl, especially when there was already a long history of viral disease outbreaks spilling over from nature. Alina Chan, a post-doctoral fellow specializing in gene therapy and cell engineering at the Broad Institute in Cambridge, Massachusetts, echoes that view. Chan says the risk of challenging the orthodoxy that SARS-CoV-2 has natural origins — an entirely plausible hypothesis, she maintains — is greatest for established scientists in infectious disease with supervisory roles and staffs to support. She herself has spent much of the last year calling for more scrutiny of a potential lab leak, claiming that as a post-doc, she has less to lose.

The vitriol also obscures a broader imperative, Relman says, which is that uncovering the virus’ origins is crucial to stopping the next pandemic. Threats from both lab accidents and natural spillovers are growing simultaneously, as humans move steadily into wild places, and new biosafety labs grow in number around the world. “This is why the origins question is so important,” Relman says.

“We need a much better sense about where to place our resources and effort,” he adds. And if a lab release for SARS-CoV-2 looks plausible, Relman says, “then it absolutely deserves a whole lot more attention.”

If SARS-CoV-2 did spill over into humans from the wild, how and where did that happen? A year into the pandemic, these remain open questions. Scientists still speculate about whether the virus passed directly into humans from infected bats (known reservoirs for hundreds of different coronaviruses), or through an intermediary animal species. The Huanan Seafood Wholesale Market in Wuhan was initially thought to be the originating site of a potential spillover, since that’s where the first cluster of Covid-19 — the disease caused by the virus — was detected. But newer evidence suggests that animal or human infections may have been circulating elsewhere for months beforehand, and the focus has since broadened to other markets in the city, wildlife farms in Southern China, and other possible scenarios, such as consuming virally-contaminated frozen meat originating in other provinces.

Importantly, the virus’ immediate ancestors have yet to be identified. The closest known relative, a coronavirus dubbed RaTG13, is genetically 96 percent similar to SARS-CoV-2....