An expert says the lab leak theory is the most plausible explanation for the origins of Covid-19 as research to find evidence the virus emerged naturally continues to prove fruitless.
Dr Alina Chan, a specialist in gene therapy and cell engineering at MIT and Harvard, says it is more likely the virus emerged from the Wuhan Institute of Virology in late 2019.
Covid-19 has since led to more than 5.3 million deaths and 271 million cases globally, with the world now struggling to contain the surging Omicron variant.
The pandemic's infancy is shrouded in secrecy thanks to Beijing's tight control on information surrounding the virus's emergence.
Authorities first pointed to the Huanan Seafood Market where the virus was believed to have been transmitted to humans from animals through an intermediary host.
However, Dr Chan, speaking to the UK's Science and Technology Select Committee, said the infamous market was unlikely the source – instead merely a super-spreading event – and there is no evidence to date that the virus came from animals.
“I think the lab origin is more likely than not," she said.
"Right now it’s not safe for people who know about the origin of the pandemic to come forward. But we live in an era where there is so much information being stored that it will eventually come out."
She said leaked information on the work at the Wuhan Institute of Virology is strong evidence to support such a theory.
"You find these scientists who said in early 2018 ‘I’m going to put horns on horses’ and at the end of 2019 a unicorn turns up in Wuhan city," she said.
Dr Chan's co-author of her book Viral: The Search for the Origin of COVID-19, Viscount Ridley, said it was "incredibly surprising" no evidence of an infected animal had been uncovered despite it being the lead theory of many scientists.
Apology after lab leak theory dismissed as 'conspiracy theory'
The lab leak theory has been categorically rejected by Beijing, with China enraged by the continued allegations.
Former US President Donald Trump and former Secretary of State Mike Pompeo regularly touted the theory, suggesting they had inside information supporting the claim. However, China accused them of politicising the pandemic.
Revered medical journal The Lancet faced criticism during the session for suppressing the theory with a letter from Peter Daszak who said it was merely a "conspiracy theory".
It later emerged he had previously worked with the Wuhan Institute of Virology and a belated memorandum came apologising for the conflict of interest.
World Health Organisation chief Tedros Adhanom Ghebreyesus faced criticism for appearing to shield China from any blame or accusations about mishandling the virus. However, he has since called for further investigations to be done into the lab leak theory, suggesting the findings of a WHO-led mission in January were insufficient.
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