Initially dismissed as conspiracy theory, the possibility that the COVID-19 is the consequence of a Chinese laboratory accident is suddenly getting a second look, writes The Telegraph.
Conspiracy theorists quickly noted, when the coronavirus pandemic first emerged in Wuhan in December 2019, that it was close to the Wuhan Institute of Virology, a leading world centre for research on coronaviruses, and that the virus had somehow “escaped”.
However, their accusations were shot down by the scientific community, which claimed “shoddy” research that they said had spread on social media. They countered that it was more probable the virus had jumped from an animal and been picked up by a human in the Wuhan wet market.
The global spotlight hovered over the wet market when it was found that many of the people who had become infected early had links to the market: by May 2020, scientists had found that the virus was 97.1% similar to a disease found in bats in China’s Yunnan province. This theory appeared to silence the “lab escape” theorists, and geneticists claiming to have found evidence of man-made inserts in the virus were shunned, while journals refused to publish their work.
In a letter to Science journal earlier this month, however, 18 of the world's top epidemiologists and geneticists from institutions including Cambridge, Harvard and Stanford, called for an independent inquiry, saying the escape theory could not be ruled out. One of them, Prof Ralph Baric of the University of North Carolina, had worked with Dr Shi Zheng-li of the Wuhan Institute of Virology, enhancing bat viruses so they could infect humans.
Another of the letter’s signatories, Prof Erik van Nimwegen from the University of Basel, said: “Reports may have created the impression that there is a consensus in the scientific community that the possibility that Sars-Cov2 leaked from a laboratory can be safely dismissed. But there is no solid scientific basis for such dismissal. Almost a year and a half after the outbreak, there is still no direct evidence available either for zoonotic spillover or for a lab leak. Moreover, the latter possibility has hardly been investigated at all – not in the least because relevant information has simply not been made available to the international scientific community.”
It has also since been discovered that a letter published in The Lancet last February “strongly condemning” the lab escape theory had been organised by Peter Daszak, president of the EcoHealth Alliance that funded coronavirus research at the Wuhan Institute of Virology. Increasingly, some scientists now believe lab escape may actually be a simpler solution than the virus jumping from a bat, particularly as the infected bat population – or intermediary host – has never been found.
One of the major problems with the zoonosis – bat jumping – theory was that coronavirus turned up oddly well adapted to infect the human upper respiratory tract. But if a virus had been altered to specifically infect humans it would make more sense, some argue.
A new unpublished research paper shows that scientists were doing exactly that in 2008. The tests, known as “gain of function” experiments, were designed to get ahead of an emerging deadly virus. In 2008, Shi’s group in Wuhan first demonstrated the ability to switch the receptor binding domains for bat and human Sars viruses, and by 2010 the Institute of Virology had embarked on “gain of function” experiments to increase the infectiousness of Sars coronavirus in humans.
By 2015, Wuhan scientists had created a highly infectious chimeric virus targeting the human upper respiratory tract. In 2018 and 2019, grants from the US National Institute of Allergy and Infectious Diseases (NIAID), show that Shi had applied to work on “virus infection experiments in humanised mice” using Sars coronaviruses to find out what changes could lead to a spillover event into humans.
Shortly before the first cases of coronavirus were reported, he said in an interview that the work had been going on for six or seven years, and warned they had created “untreatable” Sars viruses which could infect humanised mice.
“You can’t vaccinate against them,” he said. “So these are a clear and present danger.”
In the new paper, scientists also point out that the spike protein of Sars-Cov2 – which the virus uses to enter cells – has changes on the surface which would fit with manipulation through “gain of function” experiments, where high infection is the goal. The authors of the new work say the chimeric experiments in 2015 were also found to affect sweet and bitter taste receptors and could account for why people lose their sense of taste during Covid.
They even speculate that because the groups used cell lines from Henrietta Lacks – the African-American woman whose cancer cells are the source of the first immortalised human cell line – it may have enabled the virus to become more infectious to black populations.
The paper concludes that several features in coronavirus are “unlikely to be the result of natural evolution" and, combined, point to "purposive manipulation, specifically for gain of function”.
But Dr Jonathan Stoye, group leader of the Retrovirus-Host Interactions Laboratory at The Francis Crick Institute, believes a man-made explanation is unlikely, given the fast evolution of the virus. “It seems extremely improbable that changes spanning such an evolutionary distance could have occurred during virus growth in a lab,” he said. “It therefore remains most likely that the immediate ancestor to SARS-CoV-2 exists in the wild and is still to be found.”
World Health Organisation (WHO) Director-General Tedros Ghebreyesus has also said there had been insufficient scrutiny of a lab escape scenario, as has Ravi Gupta, professor of clinical microbiology at the University of Cambridge and a member of the New and Emerging Respiratory Virus Threats Advisory Group (Nervtag), who said the possibility was not adequately explored “due to lack of access to primary records by the WHO group”.
History shows that lab leaks are not new: the Sars virus escaped from a high-containment research lab in Beijing at least three times in 2004, causing local outbreaks. Several weeks ago, a US intelligence report identified three researchers at a Wuhan lab who sought treatment at a hospital after falling ill in November 2019.
A report last May said the Wuhan Institute of Virology had an emergency shutdown as early as October.
US President Joe Biden last week gave intelligence services three months to report on the origins of COVID, but this will depend on China being more open, which seems unlikely.
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