WHO scientists researching the origins of Covid in China say it is ‘extremely unlikely’ the virus leaked from a lab and have called for no further study into the theory.
Instead Peter Embarek, leader of the WHO team, said that further studies should be carried out into whether the virus was imported into the country – possibly on frozen meats sold at the market in Wuhan where the first cluster of cases was detected.
He also backed assertions from Beijing that there is no evidence of transmission ‘in Wuhan or elsewhere’ in China before December 2019 – despite mounting evidence that the virus was circulating globally months earlier than that.
The findings will be a PR coup for Beijing, which has repeatedly tried to pin the blame for a pandemic which has blighted the world outside its borders.
It will also give ammunition to WHO’s critics, who feared the investigation would be used to give legitimacy to a Chinese white-washing exercise with possibly embarrassing or incriminating evidence hidden from investigators.
Peter Embarek, lead researcher for WHO in Wuhan, has concluded Covid did not leak from a lab and has instead called for research into whether it was imported from overseas
Dr Embarek put forward four theories about how the virus infected humans: Direct transfer from source animal into people, transfer via an intermediary animal, transfer via food, and transfer via a lab leak (pictured, a chart showing each of the four routes)
China’s official timeline vs new evidence
Dec 8, 2019 – Earliest date that China has acknowledged an infection
Dec 31 – China first reported ‘pneumonia of unknown cause’ to the World Health Organisation
Jan 1, 2020 – Wuhan seafood market closed for disinfection
Jan 11 – China reported its first death
Jan 23 – Wuhan locked down
Jan 31 – WHO declared ‘outbreak of international concern’ as China admitted having thousands of cases
Feb 23 – Italy reports cluster of cases in first major outbreak in the West
Sep 2019– Blood samples are taken in a lung cancer screening trial in Italy which later test positive for coronavirus
Oct-Dec – Rise in ‘flu and pneumonia’ cases in northern Italy which could be linked to coronavirus
Nov – Sewage samples taken in Florianópolis, Brazil, suggest virus was present
Nov 10 – Milanese woman has a skin biopsy, producing a sample which later shows signs of the virus
Nov 17 – Leaked documents suggest case detected in China on this date
Dec 1 – Chinese researchers report an infection on this date in a peer-reviewed study, but it has not been acknowledged by Beijing
Dec 18 – Sewage samples taken in Milan and Turin suggest virus was circulating in the cities
Jan 2020 – Sewage samples from Barcelona suggest virus was in the city
Outlining the findings of his team’s month-long fact-finding mission, Dr Embarek said the team had failed to establish where the virus came from or how it first jumped into humans. Instead, he said the team had come up with four theories.
Researchers concluded the most likely explanation is that the virus passed from its original host animal into an intermediary animal that comes into close contact with humans, before making the leap into people.
Intermediary animals could include frozen or chilled animal products sold at markets in Wuhan, including those imported from overseas, he said.
The second most-likely theory is that the virus jumped directly from its original host into humans, and Dr Embarek put forward bats as a likely source.
But, he said, humans and bats do not come into close contact in Wuhan and swabs of various other animal species in China – including wild animals, pets, and farm animals – has failed to find the original source.
Dr Embarek called for more research to be carried out into both of these theories, and the possibility that animal products carried the virus.
The only theory he rejected out-of-hand was that the virus had leaked from a lab, saying it was ‘extremely unlikely’.
Dr Liang Wannian, the head of China’s Wuhan research team, said that testing of samples from labs around Wuhan had failed to uncover any copies of Covid, meaning the virus could not have leaked.
Instead, he also pushed the theory that frozen food could have been the source, saying his research shows Covid can survive for a long time at low temperatures – meaning it could potentially travel long distances to reach Wuhan.
While an early cluster of Covid infection was linked to Huanan Seafood Market, Dr Wannian revealed that it was not the only Wuhan market to be hit by infections.
In fact, he claimed, the earliest confirmed case of Covid on December 8 had no connection to any market within the city.
He also said that samples taken from early cases at Huanan market showed slight variations in the virus, implying that it had been present in humans for an unknown length of time before causing those infections.
Putting forward other explanations for how the virus crossed into humans, Dr Wannian called for more research into potential animal hosts.
While bats and panoglins – both animals used in traditional Chinese cuisine and medicine – had been put forward as hosts, he suggested that cats and mink could have acted as an intermediary after evidence showed they can be infected.
Dr Liang Wannian, China’s lead researcher in Wuhan, also pushed the theory that the virus could have been imported on frozen meats from overseas
He said that tens of thousands of PCR tests have been conducted on animals around China, including domestically farmed animals, wild animals, and pets.
All of the tests came back negative, he said.
Dr Wannian also rubbished theories that the virus could have leaked from a lab, claiming that there is no evidence that Covid was present at any facility in China before appearing in humans.
If the virus was not present in a lab before the outbreak, then it could not have escaped, he said.
The WHO mission is a diplomatically knotty one, which was trailed before it began by fears of a whitewash, with the US demanding a ‘robust’ probe and China firing back with a warning not to ‘politicise’ the investigation.
During the closely-monitored visit, reporters were largely kept at arms’ length from the experts, but snippets of their findings crept out over Twitter and interviews.
The experts spent one month in China, two weeks in quarantine and the same again on fieldwork.
But, already over a year after the virus emerged, some of it was of questionable relevance to their stated aim of finding the virus source, including a visit to a propaganda exhibition celebrating China’s recovery from the pandemic.
The group spent just an hour at the seafood market where many of the first reported clusters of infections emerged over a year ago.
They also appeared to spend several days inside their hotel, receiving visits from various Chinese officials without going out into the city.
The pair spoke at a joint press conference on Tuesday to present the findings of a month-long WHO probe in Wuhan, designed to find the origins of Covid
But deeper research was carried out at the Wuhan virology institute where they spent nearly four hours and said they met with Chinese scientists there including Shi Zhengli, one of China’s leading experts on bat coronaviruses and deputy director of the Wuhan lab.
Former US president Donald Trump repeated a controversial theory that a lab leak may have been the source of the pandemic.
Scientists at the laboratory conduct research on some of the world’s most dangerous diseases, including strains of bat coronaviruses similar to Covid-19.
Beijing is desperate to defang criticism of its handling of the chaotic early stages of the outbreak.
It has refocused attention at home – and abroad – on its handling of, and recovery from the outbreak.
Chinese scientists and officials have been keen to point the finger of blame outside their own borders – variously suggesting that the virus could have originated in Bangladesh, the US, Greece, Australia, India, Italy, Czech Republic, Russia or Serbia
Multiple countries have uncovered evidence that the virus was circulating months earlier than originally thought. While Beijing has tried to insist this proves the virus originated elsewhere, most scientists still think China was the origin – raising the prospect that communist officials simply hid evidence of the early spread