badcantinaのブログ

These two photos, taken in 2014 by scientist Eddie Holmes, show raccoon dogs and unknown birds caged in the Huanan Seafood Wholesale Market. GPS coordinates of these images confirm that the animals were housed in the southwest corner of the market, where researchers found evidence of the coronavirus in January 2020. Eddie Holmes

Eddie Holmes
The World Health Organization is calling on officials in China to release data that may show a link between animals and the virus that sparked the COVID-19 pandemic.

The data was posted briefly on an international database but then abruptly taken down over the weekend.


Enlarge this image
Security guards stand in front of the Huanan Seafood Wholesale Market in Wuhan, China, on Jan. 11, 2020, after the market had been closed following an outbreak of COVID-19 there. Two studies document samples of SARS-CoV-2 from stalls where live animals were sold. Noel Celis/AFP via Getty Images

Noel Celis/AFP via Getty Images
The data was from environmental samples collected at a Wuhan seafood and meat market in the early days of the pandemic. International scientists spotted the material online and made copies of it before it was taken down. The information appears to show that genetic material from raccoon dogs and the virus that causes COVID were found in the same swabs, implying that the animals may have been an initial host.

"A scientist on the team noticed the data come online by happenstance, and because they often check the GISAID database," says Alexander Crits-Christopher, senior scientist in Computational Biology at Cultivarium, a nonprofit group focused on open source tools for research. "She shared the data with an international team and realized the relevance and importance of the data. This team then immediately contacted the data generators in the hopes of open communication and collaboration. The team then immediately alerted the WHO about the presence of the data, and the WHO has helped mediate that communication. All three of the parties above have iterated a shared goal of making data and analyses as open as possible, as soon as possible."

"The big issue right now is that this data exists and that it is not readily available to the international community," says WHO epidemiologist Maria Van Kerkhove, who along with the head of the WHO is calling on Chinese officials to release all of the data they have around the potential origins of COVID. She adds that this information should have been shared years ago: "Any data that exists on the study of the origins of this pandemic need to be made available immediately."


Enlarge this image
Staff members of the Wuhan Hygiene Emergency Response Team investigate the shuttered Huanan Seafood Wholesale Market on Jan. 11, 2020, after it was linked to cases of COVID-19. Noel Celis/AFP via Getty Images

Noel Celis/AFP via Getty Images
She stressed that many more studies need to be carried out: "These studies have been recommended over many years, looking at the source of the animals of the market, looking at potential intermediate hosts, looking at breaches in biosafety biosecurity. These studies have yet to be conducted, and until they are conducted, until we have the data, we aren't able to conclusively say how this pandemic began."

Since the SARS-CoV-2 pandemic began three years ago, its origin has been a topic of much scientific — and political — debate. Two main theories exist: The virus spilled over from an animal into people, most likely in a market in Wuhan, China, or the virus came from the Wuhan Institute of Virology and spread due to some type of laboratory accident.

But there is in fact a substantial body of evidence, first published in 2022 and covered by NPR at that time, pointing to the raccoon dogs as a likely starting point for the spread of SARS-CoV-2.

In particular, scientists published two extensive, peer-reviewed papers in Science in July 2022, offering the strongest evidence to date that the COVID-19 pandemic originated in animals at a market in Wuhan, China. Specifically, they conclude that the coronavirus most likely jumped from a caged wild animal into people at the Huanan Seafood Wholesale Market, where a huge COVID-19 outbreak began in December 2019.

Neither of the Science papers provide the smoking gun — that is, an animal infected with the SARS-CoV-2 coronavirus at a market.

But they come close. They provide photographic evidence of wild animals such as raccoon dogs and a red fox, which can be infected with and shed SARS-CoV-2, sitting in cages in the market in late 2019. What's more, the caged animals are shown in or near a stall where scientists found SARS-CoV-2 virus on a number of surfaces, including on cages, carts and machines that process animals after they are slaughtered at the market.

The data in the 2022 studies paints an incredibly detailed picture of the early days of the pandemic. Photographic and genetic data pinpoint a specific stall at the market where the coronavirus likely was transmitted from an animal into people. And a genetic analysis estimates the time, within weeks, when not just one but two spillovers occurred. It calculates that the coronavirus jumped into people once in late November or early December and then again few weeks later.

At this exact same time, a huge COVID outbreak occurred at the market. Hundreds of people, working and shopping at the market, were likely infected. That outbreak is the first documented one of the pandemic, and it then spilled over into the community, as one of the Science papers shows.

At the same time, the Chinese Center for Disease Control and Prevention found two variants of the coronavirus inside the market. And an independent study, led by virologists at the University of California, San Diego, suggests these two variants didn't evolve in people, because throughout the entire pandemic, scientists have never detected a variant linking the two together. Altogether, the new studies suggest that, most likely, the two variants evolved inside animals.

Evolutionary biologist Michael Worobey helped lead two of the studies and has been at the forefront of the search for the origins of the pandemic. He has spent his career tracking down the origins of pandemics, including the origin of HIV and the 1918 flu.

Cnhg2
Jmng6
Lkmg5
Sg5Nh
Abgrt
LruI8
Sgfr6
KjJ8i
Iol9B
AbV6y
NbG54
AgYi7
WeMb5
Z5LkY
N67Yk
HgbF5
recv5