An infectious disease expert believes that Omicron variant of COVID-19 will trigger a "significant escalation" of infections that could force schools, restaurants and other industries to shut down once again.

"It's not a question of if, but when," Colin Furness, an expert in infectious disease epidemiology from the University of Toronto, told CTV National News. "I don't see how we're going to keep a lid on things."

Furness warned that governments need to update COVID-19 guidance to reflect that the virus is primary spreading through airborne transmission.

"Stop pretending that bits of Plexiglas and a blue gaping surgical mask is enough to protect anyone against anything, because it isn't."

Watch the full interview by clicking on the video at the top of this article.