George Gao
Chinese authorities secretly investigated a lab at the heart of the row over Covid's origin after the pandemic began, an ex-insider sensationally revealed today.

President Xi Jinping's communist administration has repeatedly denied the lab leak hypothesis, labelling it a smear campaign by 'anti-China' forces and insisting the virus emerged naturally.

Yet Beijing considered the theory credible enough to instigate its own formal probe, according to the former chief of the country's own public health watchdog, the equivalent of the UK Health Security Agency or Center for Disease Control and Prevention in the US.

Professor George Gao, who ran the organisation when the pandemic began towards the end of 2019, claimed the Wuhan Institute of Virology (WIV) was 'double-checked' by government-backed experts.

The BBC says Professor Gao's explosive revelation โ€” shared with them โ€” is the first acknowledgement of any internal inquiry taking place over the lab leak theory.

Discussing the possibility himself in a new podcast aimed to exploring the origins of the virus, he said: 'You can always suspect anything. That's science. Don't rule out anything.'

At first, the overwhelming opinion, shared by the world's leading experts, was that Covid crossed naturally from animals infected with a bat coronavirus.

But consensus over how the pandemic began three years ago has slowly started to shift.

The lab leak theory centres around the fact that the virus first emerged miles away from the WIV, where researchers were known to be working on coronaviruses found in bats.

No concrete proof to support either argument has ever been found, leaving experts fearing the truth will never be uncovered.

Professor Gao told Fever: The Hunt for Covid's Origin, a BBC Radio 4 series, that a formal investigation was carried out into the WIV after the start of the pandemic, although he did not specify when.

'That lab was double-checked by the experts in the field,' said the world-renowned immunologist and virologist.

Professor Gao admitted he hadn't seen the official result of the probe โ€” but added he had 'heard' the lab was given the all-clear.

'I think the conclusion is that they are following all the protocols. They haven't found [any] wrongdoing,' he said.

In response to Professor Gao's comments, China's UK Embassy said: 'The so-called "lab leak" is a lie created by anti-China forces. It is politically motivated and has no scientific basis.'

Comment: It's actually a reasonable hypothesis, even if it turns out not to be true in the end.

This isn't the first time that Professor Gao has pushed past China's official narrative of the pandemic.

Last month, he told a conference in Switzerland that while he had seen no evidence to back it up, a lab leak origin for Covid was possible.

The Oxford University-educated researcher has also warned that the true origins of Covid may never be revealed due to the issue being 'too sensitive and politicised'.

And in April he, alongside colleagues, published a bombshell paper that ruled there was no proof the virus jumped from animals to humans at a now-infamous Wuhan wet market.

Professor Gao is now vice president of the National Natural Science Foundation of China after stepping down from the his previous role last year.

His retirement from the organisation in 2022, officially stated as being due to his age, was considered unusual. Chinese officials often stay in post well into their 80s.

Once dismissed as fringe hypothesis favoured by conspiracy theorists, the possibility of Covid accidentally spreading from a lab has gained increasing traction over the course of the pandemic.

Even US intelligence officials have backed it, with FBI director Christopher Wray stating in February that the virus 'most likely' originated from a lab incident in Wuhan.

However, most experts maintain that Covid most likely emerged naturally, being transmitted from animals to humans - what is known as zoonosis.

Such theories have largely pointed to Wuhan's Huanan seafood wholesale market, where numerous species of live animals were kept and sold, as the potential site where such an infection could have taken place.

But Professor Gao, a previous critic of the Huanan market theory, has said because the search for early Covid cases in January 2020 was so heavily focused on this market and hospitals near it, officials might have missed a possible source of the virus on the other side of the city.

In February 2021, an investigation into Covid's origin by the World Health Organization said it was 'extremely unlikely' the virus leaked from a lab.

Plans for a second phase of the investigation, involving audits of laboratories in the Wuhan area, were rejected by the Chinese government.

Professor Gao said he supported the continuation of the WHO's investigation but added the body would need to 'negotiate with the government'.

The new podcast also speaks to Professor Ian Lipkin, an epidemiologist based at Columbia University in New York.

Professor Lipkin was one of five co-authors of a March 2020 paper called 'The Proximal Origin of Sars-Cov-2'.

This controversial paper has been accused of trying to shut down the idea that Covid might have leaked from a lab. It concluded: 'We do not believe that any type of laboratory-based scenario is plausible.'

But Professor Lipkin said he now has doubts over the certainty of that statement.

He told the BBC that while he stands by the idea that Covid wasn't deliberately created in a lab and a natural origin remained the most likely scenario, it wasn't the only one.

Professor Lipkin pointed to another lab, the Wuhan Centre for Disease Control, located just a few hundred metres from Huanan market, as one possible source.

This lab was known to be involved in the collection of thousands of blood and faecal samples from wild bats with staff who worked there not always wearing the recommended level of PPE while doing so.

Professor Lipkin said Covid could resultingly have 'originated outside of the market and been amplified in the market'.

Scientific debate on the origins of Covid is ongoing, with no concrete proof to support either argument ever been found.

China's secrecy โ€” in not providing vital access to scientists probing the origins and accusations of covering up evidence from the early days of the pandemic by wiping key databases โ€” has only fuelled alternative theories.

Fever: The Hunt for Covid's Origin is an eight-part podcast series starting on Radio 4 at 11am today, with new episodes to air the same time weekly.

The episode featuring Professor Gao will be the sixth in the series.

Presented by John Sudworth, the BBC's former Beijing Correspondent who reported on Wuhan when Covid first emerged, the series is the result of a three-year investigation into Covid's origins.