WASHINGTON - It's "less likely" that COVID-19 originated in a laboratory and was leaked, Peter Hotez, a vaccine expert at Baylor College of Medicine, told the national media outlet US News in an article published Tuesday.

The origin of the novel coronavirus might be related to several factors, including animal hosts, urbanization, expanding deforestation and perhaps climate change, which "may be driving the increased contact between humans and animals, or the ability of viruses to leap from animals to humans", while humans haven't fully understand their interplay, said Hotez.

To figure out "the potential animal origins of COVID-19", an interdisciplinary team of scientists from China and internationally needs to be established to "exhaustively test wild animal species, including bats and possibly domestic animals, such as livestock", he said.

After SARS in 2002 and MERS in 2012, COVID-19 might be warning people that "a new serious coronavirus epidemic is going to appear every eight to ten years", and humans need to know the origin of COVID-19 to "prevent coronavirus pandemics", said Hotez.