WUHAN, China (AP) – Coronavirus probably first appeared in humans after jumping from an animal, said a team of international and Chinese scientists looking for the origins of COVID-19, stating an alternative theory that the virus leaked from one Chinese laboratory was unlikely.
A closely watched visit by World Health Organization experts to Wuhan – the Chinese city where the first cases of coronavirus were discovered – has not drastically changed the current understanding of the early days of the pandemic, said Peter Ben Embarek, the WHO mission leader .
But “he added details to this story,” he said at a news conference as the group concluded a four-week visit to the city.
And it allowed the joint team of WHO and China to further explore the laboratory leak theory – which former President of the United States, Donald Trump, and government officials had presented without evidence – and decided it was unlikely. The Wuhan Institute of Virology is home to many different virus samples, leading to claims that it may have been the source of the original outbreak, either intentionally or accidentally.
Embarek, a WHO expert on food safety and animal diseases, said experts now consider the possibility of a leak so unlikely that it will not be suggested as a future study route. But another member of the team, Danish scientist Thea Koelsen Fischer, told reporters that team members could not rule out the possibility of further investigations and new leads.
China has already vehemently rejected the possibility of a leak and promoted other theories. Chinese and foreign experts have considered various ideas of how the disease ended in humans, leading to a pandemic that has killed more than 2.3 million people worldwide.
Embarek said the initial findings suggest that the virus most likely followed the path from a bat to another animal and then to humans, adding that it would require more research.
“The findings suggest that the hypothesis of laboratory incidents is extremely unlikely to explain the introduction of the virus into the human population,” he said.
Asked why, Embarek said that accidental releases are extremely rare and that the Wuhan Institute’s team review of laboratory operations indicated that it would be difficult for anything to escape it.
He also noted that there were no reports of this virus in any laboratory before the pandemic. Liang Wannian, the head of the Chinese side, also emphasized this, saying that there was no sample at the Wuhan institute.
The mission was intended to be an initial step in the process of understanding the origins of the virus, which the scientists postulated may have passed to humans through a wild animal, such as a pangolin or bamboo rat. Direct transmission of bats to humans or through the sale of frozen food products are also possibilities, said Embarek.
The visit of the WHO team is politically sensitive to Beijing, which is concerned with being held responsible for alleged errors in its initial response to the outbreak. An AP investigation found that the Chinese government imposed limits on research on the outbreak and ordered scientists not to speak to reporters.
Still, a WHO team member, British zoologist Peter Daszak, told the Associated Press last week who enjoyed a higher than expected level of openness and who had full access to all the locations and staff they requested.
Koelsen Fischer said he was unable to see the raw data and had to rely on an analysis of the data that was presented to her. But she said that would be true in most countries.
The team – which includes experts from 10 countries who arrived on January 14 – visited the Huanan Seafood Market, site of a first group of boxes in late 2019.
Marion Koopmans, a Dutch virologist on the team, said some animals on the market were susceptible or suspected of being susceptible to the virus, including rabbits and bamboo mice. And some can be traced back to farms or traders in regions that house the bats that carry the related virus closest to the one that causes COVID-19.
She said the next step would be to look more closely at the farms.
Liang, the head of the Chinese team, said the virus also appeared to be spreading to other parts of the city besides the market, so it is possible that the virus originated elsewhere.
The team found no evidence that the disease was spreading widely before the initial outbreak in the second half of December 2019.
“We were not able to do the research entirely, but there is no indication that there were clusters before what we saw in late December in Wuhan,” said Liang.
The WHO team’s visit took months to negotiate. China only agreed to this amid international pressure at the WHO World Health Assembly meeting last May, and Beijing continued to resist calls for a strictly independent investigation.
Although China has faced some localized resurgences of the infection since it managed to control the outbreak last year, life in Wuhan itself has returned to normal.
___
Associated Press writers Ken Moritsugu in Beijing and Jan M. Olsen in Copenhagen, Denmark contributed to this report.