The SARS-CoV-2 virus, which caused the deadly COVID-19 pandemic, first infected three scientists working at China's infamous Wuhan Institute of Virology (WIV), according to a new report that strengthens the theory of a lab leak.

"Patients zero" included Ben Hu, Ping Yu and Yan Zhu -- the scientists working on the controversial "gain-of-function" research on SARS-like viruses at the WIV, according to an investigation published on the Substack newsletter Public and Racket.

It was previously noted that some WIV scientists had developed COVID-19-like illnesses in November 2019, but their identities were not known.

"Ben Hu is essentially the next Shi Zhengli," Alina Chan, a molecular biologist at the Broad Institute of MIT and Harvard, was quoted as saying. Shi is popularly known as "the bat woman of China," and led the gain-of-function research at the WIV.

"Hu was her star pupil. He had been making chimeric SARS-like viruses and testing these in humanised mice. If I had to guess who would be doing this risky virus research and most at risk of getting accidentally infected, it would be him," Chan added.

Together, Hu and Yu researched the novel lineage of SARS-like viruses from which SARS-CoV-2 hails.

According to Jamie Metzl, a former member of the World Health Organisation's expert advisory committee on human genome editing: "It's a game changer if it can be proven that Hu got sick with COVID-19 before anyone else."

"That would be the 'smoking gun'. Hu was the lead hands-on researcher in Shi's lab," Metzl was quoted as saying. Meanwhile, the role of WIV in the origin of COVID is also "becoming clear", a report said.

"It has become increasingly clear that the Wuhan Institute of Virology was involved in the creation, promulgation, and cover-up of the COVID-19 pandemic," the Times UK quoted an anonymous US State Department investigator as saying.

In May, former Chinese CDC head Dr George Fu Gao, said that the theory that COVID-19 is the result of a lab leak should not be discounted. Gao directed China's CDC when COVID first emerged in Wuhan.

"You can always suspect anything. That's science. Don't rule out anything," Gao was quoted as saying in an interview for the BBC Radio 4 podcast 'Fever: The Hunt for COVID's Origin'.

China has since the beginning dismissed any suggestion the disease may have originated in a Wuhan laboratory.

More than two years after the pandemic that has infected over 763 million and claimed more than 6.9 million lives globally, the origins of COVID-19 remain unclear.