As interest mounts in the ‘lab leak’ hypothesis for the origin of SARS-CoV-2, more scientists are starting to take it seriously, especially because of the important implications of its actual origins.
MedPage Today reported that many experts it approached for the story were hesitant to speculate on its exact implications, they agreed that further research into its origins is important to ward off future pandemics.
A natural origin’s implications
Back in 2007, scientists who were studying coronaviruses warned: “The presence of a large reservoir of SARS-CoV–like viruses in horseshoe bats… is a time bomb. The possibility of the re-emergence of SARS and other novel viruses… should not be ignored.”
On May 26 2021, in the midst of the greatest disaster the world has faced since World War II, US President Joe Biden gave US intelligence 90 days to reach a “definitive conclusion” on the origins of SARS-CoV-2.
Vincent Racaniello, PhD, professor of microbiology and immunology at Columbia University, said finding an answer is unlikely within Biden’s deadline. After all, it took 14 years to find the ancestor of the first SARS virus in wildlife.
For Prof Racaniello, this renewed concern underscores the need for better surveillance of viruses in wildlife.
“All human viruses begin in nature. There’s an overwhelming preponderance of data that shows that, so it makes sense to look in nature when we’re looking for the source of new viruses,” Prof Racaniello told MedPage Today.
As a result of human population pressure, more viruses are spilling over into humans from nature. Examples of this include Ebola, SARS-1, MERS, and bird and swine flu. Because of the evolutionary closeness of mammals and humans, they are major pathogen sources. Rodents and bats (accounting for 20% of mammals), as well as various species of birds are good places to look. However our surveillance of wildlife is spotty, so we have “very little” understanding of the viruses these types of animals harbour, and which ones could be threats to humans, Prof Racaniello warned.
“We need to do more wildlife sampling, to find out what’s out there and what’s potentially a threat,” he said. “More investment in this could have prevented the trillions of dollars that we’ve spent to take care of this pandemic.”
A lab leak’s implications
On the other hand, Richard Ebright, PhD, a molecular biologist and professor of chemistry and chemical biology at Rutgers University in New Jersey, believes the real issue lies in addressing the potential for future pandemics that could originate from lab accidents, a discussion that “needs to begin now.”
“Irrespective of whether COVID originated in a natural accident or a lab accident, the risk of a future pandemic originating in a lab accident is real,” he told MedPage Today.
Prof Ebright explained that, in the US and other countries, only voluntary biosafety guidelines exist, and these are about preventing accidental release of pathogens. While the US has legal regulations against several pathogens that could be used as biological weapons, there are no biosecurity regulations for other pathogens. In most of the world, no biosecurity regulations exist for pathogens other than smallpox, not even voluntary ones, Prof Ebright said.
In 2017, the US implemented a bio-risk policy requiring a risk-benefit analysis before federal funding can be approved for high-risk research, such as ‘gain of function’ research that could be used to increase a pathogen’s transmissibility or pathogenicity to better understand and control it, Prof Ebright said. But this bio-risk policy has been essentially ignored by federal agencies, and the other countries with bio-risk policies only apply it to smallpox.
“Discussion now, especially among policy makers and the public, needs to turn to the inadequacy of biosafety, biosecurity, and biorisk-assessment standards worldwide, and to the essentially complete absence of biosafety regulation worldwide,” he said.
The return of the lab leak hypothesis
While evidence is largely circumstantial, the basic idea is that a laboratory at the Wuhan Institute of Virology had been experimenting on a virus called RaTG13 (a coronavirus closely related to SARS-CoV-2, which infects horseshoe bats), and genetically manipulating other horseshoe bat viruses collected around China. It is thought that one of these laboratory viruses could have infected a staffer at the institute, who then transmitted it to the broader public, Dr Ebright explained.
Following the WHO’s March 30 SARS-CoV-2 origins investigation report, there was a sudden about-face and the lab leak theory began to be taken seriously. Though investigators classified a laboratory origin as “extremely unlikely”, they said the conclusion was reached on the evidence made available.
Even the Director-General of the WHO, Dr Tedros Ghebreyesus, said at the time that he did not believe the assessment of a laboratory origin was “extensive enough,” that this hypothesis “requires further investigation,” and that “this report is a very important beginning, but it is not the end.”
“At this point in time, all scientific data related to the genome sequence of SARS-CoV-2 and the epidemiology of COVID are equally consistent with a natural-accident origin or a laboratory-accident origin,” Ebright said.
While the WHO report does not propose a follow-up study for laboratory origins, it acknowledges that both “follow-up of new evidence” and “regular administrative and internal review of high-level biosafety laboratories worldwide” is needed.
Source: MedPage Today
