The virologist who led bat research at the Wuhan lab has condemned suspicions that Covid leaked from the facility as 'filth' and claimed that nobody ever got sick there.
Shi Zhengli, also known as the Bat Woman, has been accused of conducting controversial 'gain of function' experiments which genetically modify viruses in order to better understand the risks they pose.
But she says that claims that coronavirus leaked from the Wuhan Institute of Virology were baseless, although she was unable to provide any supporting evidence.
'How on earth can I offer up evidence for something where there is no evidence?' She told The New York Times.
'I don't know how the world has come to this, constantly pouring filth on an innocent scientist,' Dr Shi added.
She said the theories were completely unsubstantiated and said it was untrue that three of her colleagues had fallen ill with Covid before the outbreak emerged.
Dr Shi Zhengli (pictured) is known as 'Bat Woman' by her colleagues because of her pioneering virus-hunting expeditions to bat caves in remote parts of China over almost two decades
Western intelligence agencies had seemingly written off the 'remote' chance that the laboratory - where research into bat-derived coronaviruses is conducted - had played a role. Pictured: Researchers in a lab at the Wuhan Institute of Virology in Wuhan in central China's Hubei province, February 2017
'The Wuhan Institute of Virology has not come across such cases,' she wrote. 'If possible, can you provide the names of the three to help us check?'
But China has blocked an independent probe of the lab and hasn't released any of the raw data from the facility, making it impossible to validate anything Dr Shi says.
Many virologists presume that Dr Shi is correct, saying it is much more likely that Covid-19 jumped from an animal to human outside of a lab setting.
But the lack of proof means that a growing number of experts and politicians are demanding a new probe and investigation of the lab leak theory.
The Trump administration attempted to raise the alarm with intelligence dumps about the lab which said researchers fell ill in the fall of 2019 with symptoms consistent with Covid-19. That was at least a month before Beijing officially reported the existence of a new respiratory illness to the world on December 31, 2019.
Among the dossiers were claims that the Bat Woman's team were working with a bat coronavirus that is 96.2 percent similar genetically to the virus that causes Covid and that the lab had secret links to Chinese military.
Beijing agreed to allow a WHO team of experts to visit Wuhan earlier this year, but only gave limited access to the lab.
The WHO's conclusion that the lab leak theory was 'highly unlikely' is not deemed credible and its report is largely regarded as a whitewash, with their fact-finding mission hamstrung by the Chinese Communist Party.
No independent research was permitted, nor were WHO officials allowed to scrutinise lab data, safety logs or records.
Even WHO's director-general, Tedros Ghebreyesus, agreed that the resulting report was unsatisfactory. Fourteen countries, including the U.S. and UK, issued a joint statement expressing concerns that the investigation had not been sufficiently thorough.
Joe Biden, who has ordered his intelligence agencies to redouble their efforts to find the origins of Covid, told a reporter at the G7 summit at the weekend: 'I have not reached a conclusion because our intelligence community is not certain yet.'
Boris Johnson echoed that sentiment saying of the lab leak theory: 'Clearly anybody sensible would want to keep an open mind about that.'
Before Covid struck, Dr Shi was regarded as foremost in her field and a symbol of China's global scientific clout.
She had gained fame as the Bat Woman for her pioneering virus-hunting expeditions to bat caves in remote parts of China over almost two decades.
Dr Shi concluded that the men had died of a fungal infection caused by a pathogen lurking in the fungus that covered the bat guano.
Dr. Robert C. Gallo, director of the Institute of Human Virology at the University of Maryland School of Medicine, told the NYT: 'She's a stellar scientist — extremely careful, with a rigorous work ethic.'
In an interview earlier this month President Joe Biden's chief medical adviser, Dr Anthony Fauci, director of the U.S. National Institute of Allergy and Infectious Diseases, agreed that a lab escape was 'a possibility'. He said he would also back a second investigation by the World Health Organisation (WHO). Pictured: The Wuhan Institute of Virology (WIV)
The first investigation in January by Western scientists, which was strictly supervised by Beijing from start to finish, resulted in a report that a Wuhan laboratory incident was 'highly unlikely' to have caused the pandemic. Pictured: Scientists at the WIV in 2017
The Wuhan Institute of Virology employs nearly 300 people and is the home to only two Chinese labs given the top bio-safety clearance, Level 4. It is the only lab in China permitted to handle deadly viruses such as ebola, bird flu and HIV.
Unlike most scientists at her level, Dr Shi is not a card-carrying member of the Communist Part, according to Chinese media.
The 57-year-old obtained her PhD from the University of Montpellier in 2000 and began the study of bats after the SARS outbreak of 2004.
'In all the work we do, if just once you can prevent the outbreak of an illness, then what we've done will be very meaningful,' she told CCTV, China's state broadcaster, in 2017.
But others argue that the risk is not worth the reward and condemn her for the gain of function research she has undertaken, whereby coronaviruses have been genetically modified to see how they behave.
In 2017, she and her colleagues published a paper which described the creation of a new hybrid bat coronavirus which was almost transmissible to humans after combining pieces of genetic code from different pathogens.
Proponents say this research helps to counter pandemics but critics say it risks creating one, and in fact many go further, claiming that Dr Shi and her team engineered Covid-19.
But Dr. Shi said their genetic modifications would never set out to make a virus more dangerous.
'My lab has never conducted or cooperated in conducting GOF experiments that enhance the virulence of viruses,' she told the NYT.
One of the viruses, originating from the anus of a horseshoe bat (pictured), was given the name RaTG13 by Dr Shi
But there has been speculation that bat viruses were not handled with the correct protocols and that some of Dr Shi's experiments were done in Level 2 labs - not the maximum safety available at the Wuhan Institute of Virology.
Dr Shi told the NYT it's acceptable to use Level 2 labs because there is no evidence to suggest bat coronaviruses directly infected humans.
But speculation has fallen on Dr Shi's research on a group of miners in Yunnan Province who suffered from a respiratory infection in 2012.
They worked inside the same cave where Dr Shi would later find bat viruses which are genetically similar to Covid-19.
Dr Shi claims that they didn't discover SARS-like coronaviruses in the cave and publish more details soon.
Critics claims she has deliberately withheld information vital to understanding the origins of the virus.
The scientists said she'd been completely open with WHO investigators who visited the lab earlier this year.
“This is no longer a question of science,” Dr Shi said. “It is speculation rooted in utter distrust.”