Covid’s natural origin theory was today seemingly dealt a huge blow — by China’s very own scientists.
In a fresh twist to the never-ending saga, Beijing-affiliated researchers ruled there was no proof to definitively say the virus jumped from animals to humans at a now-infamous market in Wuhan.
Swathes of patients struck down at the start of the pandemic visited or had links to its stalls, which sold bats, raccoon dogs, pangolins and other exotic species either proven to harbour similar coronaviruses or thought to.
As such, top virologists agreed with the Chinese government’s argument that Covid likely emerged naturally inside the busy market.
However, in one of the most eagerly-awaited papers on the topic, experts from the Chinese Center for Disease Control and Prevention said: ‘The evidence provided in this study is not sufficient to support such a hypothesis…
Studies point to Huanan Seafood Wholesale Market in Wuhan (pictured) as being the epicentre of the outbreak. Many of the earliest cases in December 2019 and January 2020 had visited the site, where live animals were sold
Ever since the pandemic began, the Huanan Seafood Market had been held up as the source of the pandemic as the earliest cases were linked to the market. Pictured: Workers in protective gear catch a giant salamander that was reported to have escaped from the Huanan Seafood Market in January 2020
‘The possibility of potential introduction of the virus to the market through infected humans, or cold chain products, cannot be ruled out yet.’
The explosive paper, sharing data that scientists across the world have demanded ever since the pandemic kicked off, suggests the virus was prevalent at the Huanan Seafood Market when the outbreak began.
But the researchers argued that people could have brought the virus to the market, which then acted as a super-spreader in December 2019.
To understand the market’s precise role in the origins of Covid, the team, including the former head of the Chinese CDC Dr George Gao, looked at samples taken from the site after the outbreak was first detected.
This included 923 samples from in and around the market and 457 from animals — including strays, their faeces and meat kept in fridges and freezers.
The paper, published in journal Nature, states that 73 of the samples taken from the market (7.9 per cent) tested positive for Covid.
While most of were concentrated in the West of the market, the virus was detected on stalls selling a range of products — from wildlife to vegetables.
The researchers said this suggests Covid ‘may have been circulating in the market’ for ‘a while’ in December 2019, leading to ‘extensive distribution’, which may have been facilitated by crowds.
Some say it’s possible the coronavirus leaked from the Wuhan Institute of Virology (pictured), where researchers were conducting controversial research on the world’s most dangerous pathogens
But none of the 457 animal samples tested positive for the virus, they said.
The researchers concluded that it ‘remains possible that the market may acted as an amplifier of transmission due to the high number of visitors every day’.
The market is less than 1km from Hankou Railway Station, described by the scientists as a ‘major travel hub’.
Sharing their results in the journal, they said: ‘These environmental samples cannot prove that the animals were infected.
‘Furthermore, even if the animals were infected, our study does not rule out human-to-animal transmission occurred.’
None of the authors were linked to the Wuhan Institute of Virology, the secretive site behind the lab leak theory.
Independent experts today said the data was one of the most important sets ‘we’ve had since the emergence of the pandemic’.
Others argued that, despite knocking back the natural origin theory, it did not give any weight to the lab leak theory because the ‘extent of circumstantial evidence is greater than one can find for the alternate hypothesis’.
The same team of Chinese scientists published an earlier version of this study back in February 2022. Yet they did not include any analysis of the genetic material of the swabs or publicly share them.
It comes after a study last month suggested that raccoon dogs sold at the market in Wuhan could be the origin of the pandemic.
The paper, which has not been peer-reviewed, found genetic material from raccoon dogs and several other animals known to harbour Covid were located in some of the same stalls where SARS-CoV-2’s genome was also present at the time of the initial outbreak.
US magazine The Atlantic, which was leaked the research, billed it as the ‘strongest evidence yet that an animal started the pandemic’.
That controversial report was based on the exact same data from this Chinese team, who dismissed the findings and insisted the question over how Covid started remained ‘open’.
Experts stumbled across the data by chance on a public data repository site, before it was suddenly removed.
In the wake of that analysis, World Health Organization officials to moan that the data ‘could have and should have been shared three years ago’.
The question of whether the global outbreak began with a spillover from wildlife sold at the market or leaked out of the Wuhan lab just eight miles across the Yangtze River has given rise to fierce debate about how to prevent the next pandemic. New studies point to a natural spillover at the Huanan wildlife market. Positive swab samples of floors, cages and counters also track the virus back to stalls in the southwestern corner of the market (bottom left), where animals with the potential to harbour Covid were sold for meat or fur at the time (bottom right)
While China has insisted the virus originated elsewhere, academics, politicians and the media have contemplated the possibility it leaked from a high-level biochemical lab in Wuhan – raising suspicions that Chinese officials simply hid evidence of the early spread
Professor Alice Hughes, a conservation biologist at the University of Hong Kong, said the new analysis ‘is incredibly weak’, has ‘major flaws’ and is littered with errors.
She said that the analysis suggests there were animals in the market that could not possibly be there, suggesting the scientists incorrectly identified the animals or that the samples were contaminated when examined in the lab.
Professor Hughes said: ‘This either relates to very poor species assignment, or contamination of the genomic samples (or both).
She added: ‘The issue of the origins of SARS-CoV-2 is so important.
‘It’s a shame there couldn’t have been more collaboration in working on this analysis, as there do appear to be errors.
‘We should be looking for further analysis on these datasets, where necessary care is applied to ensure reliable and accurate results.’
Scientists claim it is vital to understand how the Covid pandemic began to prevent future outbreaks.
Studies point to Huanan Seafood Wholesale Market in Wuhan as being the epicentre of the outbreak.
However, others believe the virus was leaked — accidentally or on purpose — from the Wuhan Institute of Virology (WIV), which was conducting experiments on live bats.
Dr Shi Zhengli, a virologist at the WIV nicknamed ‘Bat Woman’, was overseeing ‘gain of function’ experiments, which can involve purposely manipulating pathogens to make them more dangerous.
China has repeatedly denied it was to blame for the outbreak — blaming a wet market in Wuhan as the source of the outbreak and even pointing the finger at the US.
China’s secrecy — in not providing vital access to scientists probing the origins and accusations of covering up evidence from the early days of the pandemic by wiping key databases — has only added fuel to the fire.
The truth on how Covid emerged will likely never be known, however.