Nearly five years after COVID-19 first emerged, the international community has not been able to determine exactly where the virus came from. The first cases were detected in the Chinese city of Wuhan in late 2019, but there have been disputes between proponents of the two main theories. One is that the virus leaked from a Wuhan lab that studied related viruses, while the other is that people caught COVID-19 from an infected wild animal being sold at a local market.
The presence of these animals at the Huanan market had previously been disputed, despite some photographic evidence and a 2021 study. Numerous parts of one stall tested positive for the Covid virus, including "animal carts, a cage, a garbage cart, and a hair/feather removal machine," the study said. "There was more DNA from mammalian wildlife species in these samples than human DNA," it added.