Covid-19 didn't start in Wuhan wet market and 'lab leak' theory dismissed by WHO
9 February 2021, 12:09 | Updated: 9 February 2021, 14:24
The theory that Covid-19 was leaked from a top secret scientific research facility is an "extremely unlikely pathway" for the virus and will not be investigated further, a World Health Organisation team confirmed today.
Announcing findings after a period of investigation into the origins of the virus in Wuhan, China, the WHO team said the lab leak theory which has been rejected by Beijing would not be probed further.
They added that the exact source of the virus was a "work in progress" but evidence points towards a population of bats outside of Wuhan and that the virus was in circulation in "other regions" weeks before the outbreak at a wet market.
The WHO said it found evidence that the virus that causes Covid-19 could have been circulating in other regions of China "several weeks" before it was identified in the Wuhan wet market outbreak.
Investigators said there was no evidence of large outbreaks before December 2019 but that the virus was in circulation in other regions.
Liang Wannian, head of the expert Covid-19 panel at China’s National Health Commission, told the news conference that "unpublished studies" show circulation of Sars-Cov-2 preceded the initial detection of cases by several weeks.
He said that there was no "substantial" circulation of Covid in Wuhan before the late 2019 outbreak and that there was "insufficient evidence" to determine whether it had spread more widely in Wuhan before December 2019.
Investigators said that there was no evidence of any large outbreaks elsewhere prior to that time.
Dr Peter Ben Embarek, leader of the WHO investigation team, said: "We did not find evidence of large outbreaks prior to December 2019 in Wuhan or elsewhere."
But he added that the team had found some evidence of wider circulation outside the Huanan market cluster in December 2019.
Professor Liang also said the host animal that originated the Covid-19 outbreak has not yet been identified. He told the world's media that research must begin with how the virus circulated in animals before it crossed to humans.
He said the discovery of the virus suggested Sars-Cov-2 may have originated from transmission between animals, but the original "reservoir host" animal remains to be identified.
Bats and pangolins are potential candidates for transmission but coronavirus samples found in those species are not identical to Sars-Cov-2, he told the press conference.
He added that the susceptibility of minks and cats to Sars-Cov-2 suggested there may be other animals that serve as so-called "reservoir hosts", but more research is needed.
