While research shows SARS-CoV-2 wasn't made in a lab, its emergence in the same city as the WIV has raised suspicions and inspired widespread speculation. Even if it evolved naturally, for example, a popular theory suggests the virus could have escaped after researchers collected it from the wild.

After an in-depth analysis of the genetic material from hundreds of swabs taken from the walls, floors, machines and drains inside the Huanan Seafood Wholesale Market in Wuhan, China — a site that’s been described as an epicenter of early spread of Covid-19 — scientists say they now know exactly which species of animals were in the same area where investigators also found the most positive samples the virus that causes Covid-19.

Samples taken in the pandemic's early weeks reinforce hypothesis that coronavirus emerged from live animal market, not a laboratory, new study says.

“It’s one of the most important data sets on the early pandemic and on the origin of SARS-CoV-2,” says Florence Débarre, an evolutionary biologist at the the French national research agency CNRS, and co-author of the Cell analysis.

That theory is now supported by a new study analyzing more than 800 samples collected in and around the market in January 2020 as the pandemic began. Those samples show that animal species known to carry the COVID coronavirus were present in the market,