BEIJING - Experts from the World Health Organisation and China have quashed the controversial theory that the coronavirus had leaked from a Wuhan laboratory, suggesting instead that the Covid-19 virus most likely infected humans from an intermediate animal host.
Instead, further studies looking at whether the virus could have made the jump to humans from frozen animal products was needed, said Dr Embarek, in an indication of the direction of future investigations probing the origins of Covid-19.
Professor Liang Wannian, an infectious diseases expert from Tsinghua University and a member of the WHO-China joint team, said laboratories in Wuhan did not possess specimens of the Sars-CoV-2 virus prior to the outbreak, refuting conspiracy theories posited by some including former US President Donald Trump.
“If there is no existence of this virus, then there is no way it could be leaked,” he said.
Apart from the laboratory leak hypothesis, the other three scenarios that the WHO-led team explored include the virus jumping directly from an animal host; infecting humans via an intermediate animal species; and its transmission to the human population via frozen food products.
Referring to the Huanan market, Dr Embarek said the virus could have been introduced there “by a person who was infected and then spread to other people in the market – could be a trader or visitor – but it also could be the introduction of a product”.
He added that among the “more interesting products” at the market were frozen wildlife animals, including species known to be susceptible to such viruses.
“We know that the virus can persist and survive in these cold and frozen environments, but we don’t really understand if the virus can then transmit to humans and under which conditions this could happen,” said Dr Embarek, adding that further studies were required.
He added that work so far suggested that bats are a “natural reservoir” of the coronavirus, but it is unlikely that the virus made the jump directly to humans in Wuhan, since the city is not located near these bat habitats.
The team had examined other intermediate animal species that could have introduced the virus to the city, but no exact animal reservoir had been found, they said.
The team’s full findings will be published in a report to come, but their initial statements will vindicate Chinese officials, who have long bristled at the possibility that the virus could have come from a lab and countered that Covid-19 could have instead been brought into Wuhan via cold-chain logistics and frozen food products.
Members of the joint WHO-China mission speaking during a press conference on Feb 9. 2021. PHOTO: AFP
Prof Liang also said that the team had examined hospital data and patient and drug records, which do not indicate that there was widespread transmission of Covid-19 in Wuhan before the first cases were discovered in December 2019.
The team had also reviewed unpublished studies from different countries that suggested the virus was circulating in other countries weeks before it was discovered in Wuhan, said Prof Liang.
Team member Marion Koopmans, a virologist at Erasmus University Medical Centre in the Netherlands, said these studies did not provide “full evidence” that the virus could have been circulating elsewhere, but could give an indication for further investigations.
“So in the next step... we should really go and search for evidence for earlier circulation, wherever that is indicated,” Professor Koopmans said.
Key findings
Investigators from the World Health Organisation and China explored four hypotheses involving the origin of Covid-19:
1. Direct zoonotic spillover of the coronavirus from an animal reservoir to humans.
2. Introduction of the virus through an intermediate animal host, where the virus could adapt or circulate before making the jump to humans.
3. Food-related routes of transmission, or cold chain and frozen food products acting as a surface for transmission of the virus to the human population.
4. A leak or escape from a laboratory.
Their key findings
- The WHO-led team said the possibility of Covid-19 resulting from a laboratory leak was “extremely unlikely”.
- Initial spread of Covid-19 in Wuhan in December 2019, with a few sporadic cases at first then small outbreaks in clusters, is a “classic picture” of the start of an emerging outbreak.
- There is no evidence for widespread community transmission of Covid-19 before December 2019, when the first cases were discovered in Wuhan.
- The virus was most likely introduced to humans through an intermediate animal host, although investigators were not able to pinpoint an exact species.
What's next?
A full report outlining the team’s findings and recommendations will be released. But the team gave indications for further lines of study:
- Studying how the virus can infect humans from frozen food products.
- Tracing the supply chain of frozen animal products present at the Huanan market, to pinpoint a possible animal host for the coronavirus.
- Expanding the search globally to look for evidence of circulation of Covid-19 before Dec 2019.
BEIJING - Experts from the World Health Organisation and China have quashed the controversial theory that the coronavirus had leaked from a Wuhan laboratory, suggesting instead that the Covid-19 virus most likely infected humans from an intermediate animal host.
Instead, further studies looking at whether the virus could have made the jump to humans from frozen animal products was needed, said Dr Embarek, in an indication of the direction of future investigations probing the origins of Covid-19.
Professor Liang Wannian, an infectious diseases expert from Tsinghua University and a member of the WHO-China joint team, said laboratories in Wuhan did not possess specimens of the Sars-CoV-2 virus prior to the outbreak, refuting conspiracy theories posited by some including former US President Donald Trump.
“If there is no existence of this virus, then there is no way it could be leaked,” he said.
Apart from the laboratory leak hypothesis, the other three scenarios that the WHO-led team explored include the virus jumping directly from an animal host; infecting humans via an intermediate animal species; and its transmission to the human population via frozen food products.
Referring to the Huanan market, Dr Embarek said the virus could have been introduced there “by a person who was infected and then spread to other people in the market – could be a trader or visitor – but it also could be the introduction of a product”.
He added that among the “more interesting products” at the market were frozen wildlife animals, including species known to be susceptible to such viruses.
“We know that the virus can persist and survive in these cold and frozen environments, but we don’t really understand if the virus can then transmit to humans and under which conditions this could happen,” said Dr Embarek, adding that further studies were required.
He added that work so far suggested that bats are a “natural reservoir” of the coronavirus, but it is unlikely that the virus made the jump directly to humans in Wuhan, since the city is not located near these bat habitats.
The team had examined other intermediate animal species that could have introduced the virus to the city, but no exact animal reservoir had been found, they said.
The team’s full findings will be published in a report to come, but their initial statements will vindicate Chinese officials, who have long bristled at the possibility that the virus could have come from a lab and countered that Covid-19 could have instead been brought into Wuhan via cold-chain logistics and frozen food products.
Members of the joint WHO-China mission speaking during a press conference on Feb 9. 2021. PHOTO: AFP
Prof Liang also said that the team had examined hospital data and patient and drug records, which do not indicate that there was widespread transmission of Covid-19 in Wuhan before the first cases were discovered in December 2019.
The team had also reviewed unpublished studies from different countries that suggested the virus was circulating in other countries weeks before it was discovered in Wuhan, said Prof Liang.
Team member Marion Koopmans, a virologist at Erasmus University Medical Centre in the Netherlands, said these studies did not provide “full evidence” that the virus could have been circulating elsewhere, but could give an indication for further investigations.
“So in the next step... we should really go and search for evidence for earlier circulation, wherever that is indicated,” Professor Koopmans said.
Key findings
Investigators from the World Health Organisation and China explored four hypotheses involving the origin of Covid-19:
1. Direct zoonotic spillover of the coronavirus from an animal reservoir to humans.
2. Introduction of the virus through an intermediate animal host, where the virus could adapt or circulate before making the jump to humans.
3. Food-related routes of transmission, or cold chain and frozen food products acting as a surface for transmission of the virus to the human population.
4. A leak or escape from a laboratory.
Their key findings
- The WHO-led team said the possibility of Covid-19 resulting from a laboratory leak was “extremely unlikely”.
- Initial spread of Covid-19 in Wuhan in December 2019, with a few sporadic cases at first then small outbreaks in clusters, is a “classic picture” of the start of an emerging outbreak.
- There is no evidence for widespread community transmission of Covid-19 before December 2019, when the first cases were discovered in Wuhan.
- The virus was most likely introduced to humans through an intermediate animal host, although investigators were not able to pinpoint an exact species.
What's next?
A full report outlining the team’s findings and recommendations will be released. But the team gave indications for further lines of study:
- Studying how the virus can infect humans from frozen food products.
- Tracing the supply chain of frozen animal products present at the Huanan market, to pinpoint a possible animal host for the coronavirus.
- Expanding the search globally to look for evidence of circulation of Covid-19 before Dec 2019.
WUHAN (REUTERS, AFP) - The head of the World Health Organisation-led team in the central Chinese city of Wuhan probing the origins of Covid-19 said on Tuesday (Feb 9) that cold chain transmission of the virus is a possibility and warrants further investigation.
"Cold chain" refers to the transport and trade of frozen food. China has pushed the idea that the virus can be transmitted by frozen food and has repeatedly announced findings of coronavirus traces on imported food packaging.
However, Dr Peter Ben Embarek, a WHO specialist in animal diseases who leads the independent group of experts, also said the team’s nearly month-long investigation in Wuhan had not dramatically changed the picture of the outbreak.
“We know the virus can survive in conditions that are found in these cold, frozen environments, but we don’t really understand if the virus can transmit to humans” or under which conditions, he told the briefing.
Dr Embarek said it would be worthwhile to explore whether a frozen wild animal in a market setting with the right conditions could be conducive to rapid spread of the virus.
He also said investigators were looking at whether the virus was circulating earlier than first thought, and that blood samples needed to be found to conduct further research.
Lab leak unlikely
The possibility that the virus leaked from a lab – another hypothesis – was extremely unlikely and did not require further study, Dr Embarek told the briefing.
Dr Liang Wannian, an expert with China’s Health Commission, also told the press briefing that there had been no substantial spread of the virus in the city before the late 2019 outbreak.
The investigation had not yet found the animal host responsible for transferring the virus to humans, Dr Liang said. Transmission from animals was likely but so far "the reservoir hosts remain to be identified", he added.
Members of the joint WHO-China mission speaking during a press conference on Feb 9. 2021. PHOTO: AFP
Members of the team have sought to rein in expectations about the mission, with zoologist Peter Daszak saying last week that one of their aims was to “identify the next steps to fill in the gaps”.
Another team member, infectious disease expert Dominic Dwyer, said it would probably take years to fully understand the origins of Covid-19.
The United States said China needed to be more open when it comes to sharing data and samples as well as allowing access to patients, medical staff and lab workers. Beijing subsequently accused Washington of politicising a scientific mission.
NAYPYIDAW: Police fired gunshots into the air and used water cannon, tear gas and rubber bullets on Tuesday (Feb 9), as demonstrators across Myanmar defied a military ban on rallies.
Four people were hurt by rubber bullets in the capital Naypyidaw, and one of them, a woman, was in critical condition with a head wound, a doctor said.
Protests erupted for a fourth straight day against last week's coup to oust civilian leader Aung San Suu Kyi, despite a warning from the new junta that they would take action against demonstrations that threatened "stability".
Protesters confront police vehicles during a demonstration at the monument of General Aung San, the late father of detained Myanmar leader Aung San Suu Kyi in the capital Naypyidaw on Feb 9, 2021. (Photo: STR / AFP)
In Naypyidaw, the remote capital purpose built by the previous military regime, witnesses said police fired rubber bullets at protesters after earlier blasting them with water cannon.
"They fired warning shots to the sky two times, then they fired (at protesters) with rubber bullets," a resident told AFP, adding that he saw some people injured.
An AFP reporter on the ground confirmed that shots had been fired.
It remained unclear how many people were hurt, as a hospital in Naypyidaw would not allow relatives in to see their family members, said Tun Wai, who rushed there when he heard his 23-year-old son was in the operation room.
"My son was shot when he tried to use the megaphone to ask people to protest peacefully after the police used water cannon to disperse them," the 56-year-old goldsmith told AFP.
"He got hit in the back... I'm very worried about him."
In Mandalay, the country's second-biggest city, police fired tear gas to disperse protesters.
A medical team gives first aid to a man injured after police used a water cannon on protesters holding a demonstration against the military coup in Mandalay on Feb 9, 2021. (Photo: STR / AFP)
After watching hundreds of thousands of people rally in opposition to last week's coup, junta chief General Min Aung Hlaing made a televised speech on Monday evening to justify seizing power.
The military has banned gatherings of more than five people in Yangon, the nation's commercial hub, as well as Naypyidaw and other areas across the country where major rallies have erupted, including the second biggest city Mandalay.
A nighttime curfew has also been imposed at the protest hotspot sites.
Demonstrators stand off with police in riot gear at an intersection during a protest in Mandalay, Myanmar on Feb 9, 2021. (AP Photo)
But on Tuesday, fresh protests emerged in various parts of Yangon, including near the headquarters of the National League for Democracy (NLD), the party of deposed leader Aung San Suu Kyi, who has been detained by the military.
On Tuesday, Myanmar's authorities extended areas where gatherings are restricted to more parts of the country, the military's information unit said.
The areas where public gatherings of more than five people are banned and a curfew has been imposed include the commercial hub of Yangon, the capital Naypyidaw, as well as some towns in the Magwe region, Kachin state, Kayah state, Mon state and Shan State, the Facebook page of the military's True News information unit said.
Protesters face off with riot police during a demonstration against the military coup in Yangon on Feb 9, 2021. (Photo: Sai Aung Main / AFP)
NAYPYIDAW: Police fired gunshots into the air and used water cannon, tear gas and rubber bullets on Tuesday (Feb 9), as demonstrators across Myanmar defied a military ban on rallies.
Four people were hurt by rubber bullets in the capital Naypyidaw, and one of them, a woman, was in critical condition with a head wound, a doctor said.
Protests erupted for a fourth straight day against last week's coup to oust civilian leader Aung San Suu Kyi, despite a warning from the new junta that they would take action against demonstrations that threatened "stability".
Protesters confront police vehicles during a demonstration at the monument of General Aung San, the late father of detained Myanmar leader Aung San Suu Kyi in the capital Naypyidaw on Feb 9, 2021. (Photo: STR / AFP)
In Naypyidaw, the remote capital purpose built by the previous military regime, witnesses said police fired rubber bullets at protesters after earlier blasting them with water cannon.
"They fired warning shots to the sky two times, then they fired (at protesters) with rubber bullets," a resident told AFP, adding that he saw some people injured.
An AFP reporter on the ground confirmed that shots had been fired.
It remained unclear how many people were hurt, as a hospital in Naypyidaw would not allow relatives in to see their family members, said Tun Wai, who rushed there when he heard his 23-year-old son was in the operation room.
"My son was shot when he tried to use the megaphone to ask people to protest peacefully after the police used water cannon to disperse them," the 56-year-old goldsmith told AFP.
"He got hit in the back... I'm very worried about him."
In Mandalay, the country's second-biggest city, police fired tear gas to disperse protesters.
A medical team gives first aid to a man injured after police used a water cannon on protesters holding a demonstration against the military coup in Mandalay on Feb 9, 2021. (Photo: STR / AFP)
After watching hundreds of thousands of people rally in opposition to last week's coup, junta chief General Min Aung Hlaing made a televised speech on Monday evening to justify seizing power.
The military has banned gatherings of more than five people in Yangon, the nation's commercial hub, as well as Naypyidaw and other areas across the country where major rallies have erupted, including the second biggest city Mandalay.
A nighttime curfew has also been imposed at the protest hotspot sites.
Demonstrators stand off with police in riot gear at an intersection during a protest in Mandalay, Myanmar on Feb 9, 2021. (AP Photo)
But on Tuesday, fresh protests emerged in various parts of Yangon, including near the headquarters of the National League for Democracy (NLD), the party of deposed leader Aung San Suu Kyi, who has been detained by the military.
On Tuesday, Myanmar's authorities extended areas where gatherings are restricted to more parts of the country, the military's information unit said.
The areas where public gatherings of more than five people are banned and a curfew has been imposed include the commercial hub of Yangon, the capital Naypyidaw, as well as some towns in the Magwe region, Kachin state, Kayah state, Mon state and Shan State, the Facebook page of the military's True News information unit said.
Protesters face off with riot police during a demonstration against the military coup in Yangon on Feb 9, 2021. (Photo: Sai Aung Main / AFP)
