The team analysed hundreds of genetic samples to conclude that the virus jumped from animals to humans in a food market in Wuhan, China.
Angie Rasmussen, a study co-author and virologist at the University of Saskatchewan's Vaccine and Infection Disease Organization, told the CBC "it's very difficult to explain any other way, besides that virus was brought there with those live animals and it spilled over, twice actually, into the human population at the market.”
The study has been published in Cell, scientific journal.