The WHO mission to China to uncover the origins of the coronavirus has failed to identify the source of the pandemic but the team on Tuesday ruled out the Wuhan lab-leak theory propagated by Donald Trump.
Experts believe the disease — which has killed more than 2.3 million people worldwide — originated in bats and could have been transmitted to humans via another mammal.
World Health Organization foreign expert Peter Ben Embarek said identifying the animal pathway remains a “work in progress”, and the absence of bats in the Wuhan area dimmed the likelihood of direct transmission.
It was “most likely” to have come from an intermediary species, he said. He also backed up China’s position that there was no evidence of “large outbreaks” in Wuhan before December when the first official cases were recorded.
Animals such as rabbits, ferrets and bamboo rats could be the intermediary, another team member Marion Koopmans added, saying they might be an “entry point” for further investigations.
Liang Wannian, head of the China side of the joint mission, said animal transmission remained the likely route, but “the reservoir hosts remain to be identified”.
Ben Embarek quashed the theory that a leak from a virology lab in Wuhan could have caused the pandemic.
“The laboratory incident hypothesis is extremely unlikely,” he said. It “is not in the hypotheses that we will suggest for future studies”.
The mission was a diplomatically knotty one — presaged by fears of a whitewash — with the US demanding a “robust” probe and China firing back with a warning not to “politicise” the investigation.
The WHO experts spent a month in China including two weeks in quarantine.
Liang said studies showed the virus could be “carried long-distance on cold chain products”, appearing to nudge towards the theory the virus was imported — an idea that has abounded in China in recent months.
Ben Embarek said “the virus can persist and survive in conditions that are found in these cold and frozen environments”.