Chinese virologist Tong Yigang has denied the rhetoric claiming the virus that caused the COVID-19 pandemic could have been leaked from a lab. He says it's an easy story to tell by people who are not experts in virology. CGTN interviews Tong Yigang, the co-leader of the WHO-China joint team's animals and environment group and professor at Beijing University of Chemical Technology, they discussed some of the most popular hypotheses about COVID-19's origins.