We have 3 live coronaviruses; none match SARS-CoV-2: Wuhan lab

Yanyi told Chinese state media CGTN that the institute has isolated and obtained CoVs over the years since it started researching the origins of SARS.

She said WIV currently has three strains of live viruses. One of them is 96% similar to SARS, the highest similarity among the three, she said.

She added, "But their highest similarity to SARS-CoV-2 only reaches 79.8%."

Yanyi also said that the novel CoV mentioned in the Nature journal in April 2018 is named SADS, which "mainly causes diarrhea and death among piglets" and has only 50% genetic similarity to SARS-CoV-2.

She also refuted allegations that the SARS-CoV-2 may have evolved from RaTG-13, a bat CoV studied by WIV that is the "closest described relative" of the virus responsible for COVID-19.

Yanyi said the WIV never isolated or obtained RaTG-13 as a live virus.

The virus has a 96.2% similarity to SARS-CoV-2 and varies on 1,100 nucleotide positions. "The difference of over 1,100 positions is huge," she said.

She also cited evolutionary virologist Edward Holmes, who said that it could take RaTG-13 50 years to naturally evolve into SARS-CoV-2.

Since the coronavirus outbreak started late last year, there have been rumors that the virus originated from WIV.

These claims were brought into the mainstream when the United States President Donald Trump and US Secretary of State Mike Pompeo claimed to have evidence that the virus leaked from WIV.

The World Health Organization said the US offered no evidence to support the "speculative" claims.

Thus far, it is believed that SARS-CoV-2 originated from bats and crossed over to humans, possibly through an intermediary species like pangolins. However, the origins of the virus are still being investigated.

Earlier, a report in US media claimed that an intern at WIV had accidentally leaked the virus from the lab.

The virus has killed 3.42 lakh people globally and infected 53.24 lakh.