The World Health Organization (WHO) chief has called for further investigation into a popular theory that COVID-19 originated from a laboratory leak in China. The director-general of the WHO Tedros Adhanom Ghebreyesus also rebuked China for not divulging key data.
China has always flatly rejected the hypothesis. And the team of international experts sent to Wuhan by the WHO earlier this year to probe the pandemic's origins have also all but ruled it out.
They said the SARS-CoV-2 virus that causes COVID-19 disease most probably jumped from bats to humans via an intermediary animal, judging a lab leak to be an "extremely unlikely" source.
The WHO chief said March 30 the probe into Wuhan's virology labs had not gone far enough. He said the WHO was prepared to launch a fresh investigation.
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"Although the team has concluded that a laboratory leak is the least likely hypothesis, this requires further investigation, potentially with additional missions involving specialist experts, which I am ready to deploy," he said.
I do not believe that this assessment was extensive enough, he told the UN health agency's 194 member states, in a briefing on the COVID-19 origins report.
"As far as WHO is concerned, all hypotheses remain on the table. This report is a very important beginning, but it is not the end. We have not yet found the source of the virus, and we must continue to follow the science and leave no stone unturned as we do," he added.
Tedros also urged China to be more forthcoming with data -- a call echoed by several countries led by the United States, Britain and Japan.
Tedros said the Wuhan mission found that the first detected case had symptom onset on December 8, 2019 -- but to understand the earliest cases, scientists would benefit from full access to data stretching back to at least September 2019.
The team "expressed the difficulties they encountered in accessing raw data. I expect future collaborative studies to include more timely and comprehensive data sharing," said Tedros.
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After the WHO report, the United States, Japan, Canada, South Korea, Australia, Israel, Britain and seven other European countries issued a joint statement voicing concerns that the investigation "was significantly delayed and lacked access to complete, original data and samples".
Independent experts needed "full access to all pertinent human, animal, and environmental data, research, and personnel", they said.
In response, China's foreign ministry said in a statement: "Actions politicising this search for the origins will only seriously hinder global cooperation in this regard, undermine the global anti-epidemic efforts and cause more loss of life."
(With inputs from agencies)Click here for Moneycontrol's full coverage of the COVID-19 outbreak