New evidence indicating that raccoon dogs from the Huanan Seafood Market in Wuhan may have been infected with SARS CoV2 in January 2020 was published on a shared database by China’s Centers for Disease Control and Prevention in January  – but removed recently after scientists started asking questions.

This was revealed at a media briefing on Friday by World Health Organization’s (WHO) Director-General Dr Tedros Adhanom Ghebreyusus.

“This data could have, and should have, been shared three years ago,” Tedros chastised, as he appealed to China to “be transparent” in sharing data about the origins of the COVID-19 pandemic.

WHO had only become aware of the data last Sunday from China CDC relating to samples taken at the Huanan market in Wuhan in 2020, said Tedros – although this had been published on a shared GSAID online database in late January, but “taken down again recently”. 

While the data was online, scientists from a number of countries downloaded that data and analysed it, and their findings were reported earlier this week by The Atlantic.

“A new analysis of genetic sequences collected from the market shows that raccoon dogs being illegally sold at the venue could have been carrying and possibly shedding the virus at the end of 2019,” according to the publication.

The Strongest Evidence Yet That an Animal Started the Pandemic ⁦@TheAtlantic⁩ I remain baffled why any other theory has credibility? The reason we began a coronavirus vaccine program was bc of SARS 2002 and MERS 2012 and realized crap a 3rd is coming https://t.co/yhacRRKU73

— Prof Peter Hotez MD PhD (@PeterHotez) March 17, 2023

Positive swabs

This evidence came from swabs of the market that had tested positive for SARS-CoV2, which also included genetic material from raccoon dogs.

The international team that had assembled the analysis consisted of “virologists, genomicists, and evolutionary biologists”, according to The Atlantic.

The evidence may finally point to the “Animal X” vector that scientists examining the orgins of the virus believe was the most likely conduit for SARS-CoV2 between carrier bats and humans – rather than the laboratory accident theory that has gained currency recently.

“As soon as we became aware of this data, we contacted the Chinese CDC and urged them to share it with WHO and the international scientific community so it can be analysed,” said Tedros. 

The WHO also convened the Scientific Advisory Group on the Origins of Novel Pathogens (SAGO) on Tuesday and asked both the scientists who had analysed the data and China CDC  to present their analysis of the data to the group.

“This data do not provide a definitive answer to the question of how the pandemic began, but every piece of data is important in moving us closer to that answer, and every piece of data relating to studying the origins of COVID-19 needs to be shared with the international community immediately,” said Tedros.

“We continue to call on China to be transparent in sharing data and to conduct the necessary investigations and share the results. 

“Understanding how the pandemic began remains both a moral and scientific imperative.”

Molecular evidence

Dr Maria van Kerkhove, WHO lead on COVID-19, said that the scientists had told SAGO this week that there was “molecular evidence” that some of the animals sold at the Huanan Market, including raccoon dogs, “were susceptible to SARS CoV2” – evidence that had been missing until now.

“We need to make clear that the virus has not been identified in an animal in the market or in animal samples from the market, nor have we actually found the animals that infected humans,” stressed Van Kerkhove.

“What this does is provides clues to help us understand what may have happened. One of the big pieces of information that we do not have at the present time is the source of where these animals came from. Where these animals traded? Were they the wild animals or domestic animals where they farmed, where were they farmed?”

China CDC needs to explain

“The big issue right now is that this data exists and that it is not readily available to the international community,” she said.

She said that China CDC needed to explain why it had taken down the data, as all the WHO knew was that it had been uploaded to the site as part of their work and in writing a publication, a pre-print of which was available.

“I don’t know the situation or the circumstances in which the data was released and taken down,” she added.

“Unfortunately, this doesn’t give us the answer of how the pandemic began, but it does provide more clues,” said Van Kerkhove, who reiterated that there are many more studies that need to be carried out. 

“Right now, there are several hypotheses that need to be examined, including how the virus entered the human population, either from a bat through an intermediate host, or through a biosecurity breach from a lab and we don’t have a definitive answer of how the pandemic began,” she said.

Earlier evidence of links to raccoon dogs

This is not the first time, by any means, that infected racoon dogs have been linked to the early stages of the SARS-CoV2 outbreak. In July 2022, Health Policy Watch reported on research led by the University of Arizona’s Michael Worobey, that suggested that mammals in the Wuhan market place, including racoon dogs, were carrying the infection in early 2020.

The Science Magazine study found that SARS-CoV2 susceptible mammals, such as red foxes, hog badgers, and common racoon dogs, were sold at the market in late 2019 and that SARS-CoV2 environmental samples were  found in cages which had previously housed the racoon dogs, as well as other equipment used around the mammals and vendors selling those live mammals in early 2020.

The clusters of early cases around the market also occured at a frequency that was far higher than could be expected in comparison to the volumes and frequency of visitors to other major commercial locations in the city, Worobey’s study found.

The researchers also found that both early lineages of SARS-CoV-2, dubbed A and B were “geographically associated” with the market: “Until a report in a recent preprint, only lineage B sequences had been sampled at the Huanan market,” the researchers added.

“If SARS-CoV2 did not emerge at the Huanan market, how surprised should we be at the coincidence of finding the first cluster of a new respiratory virus at – of all places – one of a handful of markets in a city of 11 million,” said Michael Worobey of the University of Arizona and one of the authors of the study, said in a tweet on the study.

Image Credits: Nature , Arend Kuester/Flickr.