The World Health Organisation has rejected claims from the US that the coronavirus outbreak originated at a Chinese lab, saying there is no evidence to support the “speculative” theory.
On Sunday (local time), Donald Trump’s government continued its attack on China, with US Secretary of State Mike Pompeo saying it had “enormous evidence” the virus came from the Wuhan Institute of Virology.
Yet the WHO, who the US has accused of siding with China amid the outbreak, said it was not aware of any evidence supporting the claim.
"We have not received any data or specific evidence from the United States government relating to the purported origin of the virus – so from our perspective, this remains speculative," WHO emergencies director Michael Ryan said on Monday (local time).
Scientists believe the killer virus jumped from animals to humans, emerging in China late last year, possibly from a market in Wuhan selling exotic animals for meat.
But US President Donald Trump, increasingly critical of China's management of the first outbreak, claims to have proof it started in a Wuhan laboratory.
China has strongly refuted Mr Pompeo and Mr Trump’s claims.
"Like any evidence-based organisation, we would be very willing to receive any information that purports to the origin of the virus," Ryan said, stressing that this was "a very important piece of public health information for future control.
"If that data and evidence is available, then it will be for the United States government to decide whether and when it can be shared, but it is difficult for the WHO to operate in an information vacuum in that regard," he added.
The relationship between the US and the WHO has been severely strained, especially following Mr Trump’s decision to pull the US’s funding to the WHO, worth US$400 million ($622 million) annually.
Mr Trump has accused the UN health agency it initially downplayed the seriousness of the outbreak to shield China.
WHO suggests virus transferred to humans naturally
The WHO has repeatedly said the virus clearly appears to have originated naturally from an animal source.
WHO expert Maria Van Kerkhove stressed during Monday's briefing that there were some 15,000 full genome sequences of the novel coronavirus available, and "from all of the evidence that we have seen... this virus is of natural origin".
While coronaviruses generally originate in bats, both Van Kerkhove and Ryan stressed the importance of discovering how the virus that causes COVID-19 crossed over to humans, and what animal served as an "intermediary host" along the way.
"We need to understand more about that natural origin, and particularly about intermediate hosts," Ryan said.
It was important to know "so that we can put in place the right public health and animal-human interface policies that will prevent this happening again", he stressed.
Leave politics out of it, WHO warns
The WHO said last week it wanted to be invited to take part in Chinese investigations into the animal origins of the pandemic, which in a matter of months has killed more than 250,000 people worldwide.
"We have offered, as we do with every case in every country, assistance with carrying out those investigations," Ryan said Monday.
"We can learn from Chinese scientists," he said.
But he warned that if questions about the virus origin were "projected as aggressive investigation of wrongdoing, then I believe that's much more difficult to deal with. That is a political issue.
"Science needs to be at the centre," he said.
"If we have a science-based investigation and a science-based enquiry as to what the origin species and the intermediate species are, then that will benefit everybody on the planet."
Calls for an independent investigation into the origins of the virus have been a contentious issue in recent weeks, with Australia’s prime minister Scott Morrison one of the more vocal world leaders on the matter.
His stance has prompted an ugly back-and-forth with China, with the Chinese Ambassador in Sydney Cheng Jingye threatening China would boycott Australian exports.
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