The idea that the coronavirus pandemic originated accidentally via Chinese laboratory workers has surfaced again, this time in a documentary aired by Danish TV on Thursday.
China has reacted furiously to any suggestions that the pandemic, which has killed at least 4.3 million people since emerging in the city of Wuhan in December 2019, was caused by malpractice involving one of its laboratories.
But this is part of the “probable” assumptions, according to the head of the World Health Organization mission investigating the origins of the pandemic.
“An employee of the lab gets infected while working in a bat cave collecting samples. Such a scenario, while being a lab leak, would also fit our first hypothesis of direct transmission of the virus from bat to human. This is a hypothesis that we consider to be likely,” Peter Ben Embarek told the Danish public channel TV2.
The first phase of the WHO study, conducted at the start of the year, concluded on March 29 that the hypothesis of a laboratory incident remained “extremely unlikely”.
However, Embarek said it had been difficult for his team to discuss this theory with Chinese scientists.
But the WHO scientist pointed out that none of the types of bats suspected to have been the reservoir for the SARS-CoV-2 virus that causes COVID-19 lives in the wild in the Wuhan region.
The only people likely to have approached these types of bats are employees of the city laboratories, he said.
The WHO on Thursday urged China to share raw data from the earliest COVID-19 cases to assist the pandemic origins probe – and release data to address the lab leak theory.
The global health agency also urged all countries to depoliticise the search for the origins of the pandemic.
In its statement, the WHO said the search for the pandemic’s origins “should not be an exercise in attributing blame, finger-pointing or political point-scoring”.
Long derided as a right-wing conspiracy theory and vehemently rejected by Beijing, the lab leak hypothesis has been gaining momentum.
It was a favourite under former US President Donald Trump, but his successor Joe Biden is also keen to see this line of inquiry pursued.
Biden has ordered a review of US intelligence and increasing numbers of scientists are calling for an independent investigation to be conducted by authorities beyond the WHO.
Jamie Metzl, who sits on a WHO advisory board on human genome editing and who has been leading efforts calling for an independent investigation on how COVID-19 started, described Embarek’s comments as “a game-changer”, describing his earlier declaration that a lab leak was unlikely “shameful”.
“It’s even more significant that the international expert team who stated with such confidence in the February Wuhan press event that a lab origin was unlikely themselves believed this was not the case and were simply trying to assuage their Chinese government-affiliated hosts,” said Metzl.
All of the scientists on the WHO-led team were approved by China and the team’s agenda and final report were also vetted by the Chinese government.
Embarek told TV2 the purpose of the WHO team’s visit was “collaboration and discussion” with China.
In recent weeks, WHO chief Tedros Adhanom Ghebreyesus has acknowledged it was “ premature ” to rule out a possible lab leak as the source of COVID-19, saying last month that he was asking China to be more transparent about the early days of the pandemic.
“I was a lab technician myself. I’m an immunologist and I have worked in the lab and lab accidents happen,” Tedros said. “It’s common.”