By Emily Wang Fujiyama

The coronavirus most likely first appeared in humans after jumping from an animal, a team of international and Chinese scientists looking for the origins of COVID-19 said Tuesday, dismissing as unlikely an alternate theory that the virus leaked from a Chinese lab.

A closely watched visit by World Health Organization experts to Wuhan — the Chinese city where the first coronavirus cases were discovered — did not dramatically change the current understanding of the early days of the pandemic, said Peter Ben Embarek, the leader of the WHO mission.

But it did “add details to that story,” he said at a news conference as the group wrapped up a nearly four-week visit to the city.

And it allowed the joint Chinese-WHO team to rule out one theory on the origins of the virus. The Wuhan Institute of Virology has collected many virus samples, leading to allegations that it may have been the source of the original outbreak, whether on purpose or accidentally.

But experts now consider the possibility of such a leak so improbable that it will not be suggested as an avenue of future study, said Embarek, a WHO food safety and animal diseases expert.

China had already strongly rejected that possibility and has promoted other theories. The Chinese and foreign experts considered several ideas for how the disease first ended up in humans, leading to a pandemic that has now killed more than 2.3 million people worldwide.

Embarek said the initial findings suggest the most likely pathway the virus followed was from a bat to another animal and then to humans, adding that would require further research.

“The findings suggest that the laboratory incidents hypothesis is extremely unlikely to explain the introduction of the virus to the human population," he said.

The mission was intended to be an initial step in the process of understanding the origins of the virus, which scientists have posited may have passed to humans through a wild animal, such as a pangolin or bamboo rat. Transmission directly from bats to humans or through the trade in frozen food products are also possibilities, Embarek said.

The WHO team's visit is politically sensitive for Beijing, which is concerned about being blamed for alleged missteps in its early response to the outbreak. An AP investigation has found that the Chinese government put limits on research into the outbreak and ordered scientists not to speak to reporters.

The team — which includes experts from 10 countries who arrived on Jan. 14 — visited the Huanan Seafood Market, the site of an early cluster of cases in late 2019.

Marion Koopmans, a Dutch virologist on the team, said that some animals at the market were susceptible or suspected to be susceptible to the virus, including rabbits and bamboo rats. And some could be traced to farms or traders in regions that are home to the bats that carry the closest related virus to the one that causes COVID-19.

She said the next step would be to look more closely at farms.

Liang Wannian, the head of the Chinese side, said the virus also appeared to have been spreading in other parts of the city than the market, so it remains possible that the virus originated elsewhere.

The team found no evidence that the disease was spreading widely any earlier than the initial outbreak in the second half of December 2019.

“We haven’t been able to fully do the research, but there is no indication there were clusters before what we saw happen in the later part of December in Wuhan,” Liang said.

Another member of the WHO team, British-born zoologist Peter Daszak, told The Associated Press late last week that they enjoyed a greater level of openness than they had anticipated, and that they were granted full access to all sites and personnel they requested.

The visit by the WHO team took months to negotiate. China only agreed to it amid international pressure at the WHO's World Health Assembly meeting last May, and Beijing has continued to resist calls for a strictly independent investigation.

While China has weathered some localized resurgences of infection since getting the outbreak under control last year, life in Wuhan itself has largely returned to normal.

___

Associated Press writer Ken Moritsugu in Beijing contributed to this report.

Share:
More In Science
Amazon To Launch First Internet Satellites By 2022
Amazon plans to launch its first prototype satellites for Project Kuiper, an internet-from-space venture, in 2022. It's the first major step in the e-commerce giant's plan to rival SpaceX by building a network of satellites in space, providing internet to rural, underserved communities around the world. Loren Grush, senior science reporter for the Verge, discusses the project and how it could transform internet access moving forward.
FDA Delays Decision On Moderna Vaccine For Kids, Probing Risk Of Heart Problem
The FDA is assessing whether the Moderna vaccine can cause heart problems in adolescents. Professor Peter Pitts, founder of the Center for Medicine in the Public Interest and former FDA Associate Commissioner, discusses what the FDA is looking into and what it means for the millions of kids yet to be vaccinated.
Pfizer Posts Earnings Beat Thanks to Solid Vaccine Sales
Pfizer posted an earnings beat in its third quarter, with revenue soaring over 134% thanks to solid Covid-19 vaccine sales. Pfizer also raised its outlook for the full-year, expecting revenue to surpass $80 billion. Peter Andersen, CEO & founder of Andersen Capital Management, joined Cheddar Movers to discuss.
Monsters of the Deep Explained; Connecting the World's Oceans
Cheddar gets a look at Curiosity Stream's 'Ancient Oceans'; Deep-sea biologist Heather Bracken-Grissom sheds light on some of the monsters that we can and cannot explain lurking in the darkness of the ocean's depths; Tim Janssen, CEO of Sofar Ocean, discusses Sofar Ocean's latest round of Series B funding, and how Sofar Ocean is helping connect all five oceans to help everything from climate change to the global shipping industry.
The Company Connecting the World's Oceans
Tim Janssen, CEO of Sofar Ocean, joins 'Cheddar Reveals' to discuss Sofar Ocean's latest round of Series B funding, and how Sofar Ocean is helping connect all five oceans to help everything from climate change to the global shipping industry.
Monsters and Mysteries of the Deep Sea
Deep-sea biologist Heather Bracken-Grissom joins 'Cheddar Reveals' to shed light on some of the monsters that we can and cannot explain lurking in the darkness of the ocean's depths.
COP26 Summit In Glasglow Officially Underway
Leaders around the world have come together to discuss plans to bring action towards the Paris Agreement along with solutions on how to solve the evolving climate change crisis at the COP26 Summit. President and CEO of Center for International Environmental Law Carroll Muffett, joined Cheddar to discuss more.
What's Next for World Leaders After COP26 Commitments to Abate Climate Change
Rachel Cleetus, the policy director and lead economist of the climate and energy program for the Union of Concerned Scientists, joined Cheddar to break down some of the key goals from the COP26 summit and why leaders must focus on the science of climate change instead of getting bogged down by petty politics and the fossil fuel industry. "The main thing they have to do, make sure we're cutting our emissions sharply within this decade because the science shows that we have to cut global emissions in half by 2030 if we're going to meet our goals of averting some of the most catastrophic impacts of climate change," she said.
Why Sea Walls Alone Won't Save Our Cities From Rising Seas
Coastal cities around the world are grappling with sea level rise. And building a seawall? Not so fast. While a sea wall can be effective in certain scenarios, it can make the effects of sea level rise worse. That’s why municipalities are looking into creative alternatives.
Load More