When researchers tested surfaces at the market for the virus’ genetic material, there was one stall with the most positives, including in a cage where one researcher had previously seen mammals called raccoon dogs being kept.
The findings are “as close to having the virus in an animal as you can get,” Robert Garry, a professor of microbiology and immunology at Tulane Medical School, told CNN.
Garry was co-author on the study that found at least two zoonotic or animal-transmission events. It notes that the pandemic began with two major viral lineages, called A and B, although it says there were probably even more forms of the virus “that failed to establish in humans.” Lineage B is the more common of the two and the only one that had previously been found at the market, but the study says lineage A was also circulating around the area early in the outbreak.
The virus most likely started with at least two animal transmissions, with a raccoon dog or another mammal serving as the intermediate host before it spread to humans, the study says.