An expert from the World Health Organization on Tuesday rejected the possibility of the novel coronavirus having accidentally leaked from a controversial laboratory in the central Chinese city of Wuhan, saying it is "extremely unlikely."
The virus most probably jumped to humans via an intermediary species, Peter Ben Embarek, the leader of the WHO team and a food safety specialist, said at a press conference after its joint investigation with Chinese experts.
"The findings suggest that the laboratory incidents hypothesis is extremely unlikely to explain the introduction of the virus to the human population," Embarek said.
The administration of former U.S. President Donald Trump advanced a theory that the Wuhan Institute of Virology might be the birth of the virus, claiming some researchers there developed symptoms consistent with COVID-19 in the fall of 2019.
As China has rebuffed the accusation, all eyes were on how the WHO group would settle the matter that further sparked tensions between Washington and Beijing, which have been at odds over several issues such as trade, Hong Kong, Taiwan and the South China Sea.
Liang Wannian, a member of the WHO-China study team, also said at the same news conference that it remains unclear how a virus cluster erupted in Wuhan.
"The spread of infection may have occurred in Wuhan in December 2019," Liang said, indicating that he suspects the virus could have been circulating in other areas before it was detected in the city.
After quarantining for two weeks, the WHO experts began a full-fledged probe in late January in a bid to identify the origins of the virus.
The WHO group last Wednesday visited the laboratory -- known for having studied a coronavirus triggering the severe acute respiratory syndrome, or SARS.
Although the investigation was closed to the public, one of the experts told Kyodo News that the team observed main research rooms there and talked with Shi Zhengli, a virologist famous for her work on coronavirus in bats.
On Jan. 31, the group also carried out a one-hour probe into a Wuhan market, where many people were confirmed to have contracted the new virus in the early days of the outbreak.
The market, at which wild animals including bats and snakes had been traded alongside seafood, has been closed since January 2020. It has been sanitized thoroughly by Chinese authorities.
Skepticism grew that the WHO investigation would help trace the sources of the virus, as more than a year has passed since the first infection case was spotted in Wuhan, a business and transportation hub with a population of some 11 million.
The WHO tried to clarify the process of how bats, believed to be the main natural host of the virus, passed it to other animals, sources close to the matter said.
"Our initial findings suggest that the introduction through an intermediary host species is the most likely pathway and one that will require more studies and more specific targeted research," Embarek said.
While the WHO team had originally planned to visit China in early January, its arrival was delayed after it took the experts longer to gain permission to enter the country.
WHO Director General Tedros Ghebreyesus said earlier that he was "very disappointed" with China about the team's delay in getting into the nation.
The WHO sent a small group of experts to China for a preliminary probe in July last year, but they did not visit the market or the laboratory in Wuhan.
So far, the novel coronavirus has infected more than 106 million people and killed over 2.3 million worldwide, according to a tally by Johns Hopkins University.
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