These wildlife farms, many of them in or around the southern Chinese province of Yunnan, were likely supplying animals to vendors at the Huanan Seafood Wholesale Market in Wuhan, where early cases of COVID-19 were discovered last year, Peter Daszak, a disease ecologist on the WHO team that traveled to China, told NPR. Some of these wild animals could have been infected with SARS-CoV-2 from bats in the area.
The WHO is expected to release its findings in a report in the coming weeks.
In January, a WHO team of experts traveled to China to probe how the deadly pandemic, which has now infected more than 120 million people and killed 2.6 million worldwide, first started, Live Science previously reported. A rash of conspiracy theories have been spread about the origin of the virus, including that the virus escaped from a Wuhan lab. Last month, the WHO investigators dismissed that explanation.
The general consensus among scientists was that the coronavirus was circulating in bats and hopped to humans, likely through an intermediate species. That's exactly what the WHO investigations found: The virus likely passed from bats in southern China to animals in wildlife farms, and then to humans.
The wildlife farms are part of a project that the Chinese government has been promoting for 20 years to lift rural populations out of poverty and close the rural-urban divide, according to Daszak and NPR.
"They take exotic animals, like civets, porcupines, pangolins, raccoon dogs and bamboo rats, and they breed them in captivity," Daszak told NPR.
But in February 2020, China shut down those farms, likely because the Chinese government thought that they were part of the transmission pathway from bats to humans, Daszak said. The government sent out instructions to farmers about how to bury, kill or burn the animals in a way that wouldn't spread disease, Daszak told NPR.
Many of these farms breed animals that can carry coronaviruses, including civets, cats and pangolins. Most are located in or near the Yunnan province in southern China, where scientists previously discovered a bat virus that's 96% similar to SARS-CoV-2, according to NPR. The WHO still doesn't know what animal carried the virus from bats to humans.
"I do think that SARS-CoV-2 first got into people in South China. It’s looking that way," Daszak told NPR. The WHO also found evidence that these wildlife farms were supplying vendors at the Huanan Seafood Wholesale Market.
"China closes that pathway down for a reason," Daszak said. Namely, that they likely thought that this was the most likely path of transmission, which is also what the WHO report will conclude, he added.
You can read the whole story on NPR.
Originally published on Live Science.
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Yasemin is a staff writer at Live Science, covering health, neuroscience and biology. Her work has appeared in Scientific American, Science and the San Jose Mercury News. She has a bachelor's degree in biomedical engineering from the University of Connecticut and a graduate certificate in science communication from the University of California, Santa Cruz.