Moderna Inc. Chief Medical Officer Paul Burton said he suspects the new omicron coronavirus variant may elude current vaccines, and if so, a reformulated shot could be available early in the new year.

"We should know about the ability of the current vaccine to provide protection in the next couple of weeks," Burton said Sunday on the BBC's "Andrew Marr Show."

"If we have to make a brand new vaccine, I think that's going to be early 2022 before that's really going to be available in large quantities," he said. "The remarkable thing about the mRNA vaccines, the Moderna platform, is that we can move very fast," he said.

The Cambridge, Massachusetts-based biotech company mobilized "hundreds" of staff early on Thursday, Thanksgiving Day in the U.S., after news of the omicron variant spread.

Protection should still exist, depending on how long ago a person was vaccinated, and for now the best advice is to take one of the current Covid-19 vaccines, Burton said.

"If people are on the fence, and you haven't been vaccinated, get vaccinated," he said. "This is a dangerous looking virus, but I think we have many tools in our armamentarium now to fight it."

The emergence of the omicron strain has seen countries rush to clamp down on travel from southern Africa. Fears that it could exacerbate a winter Covid surge in the northern hemisphere and undermine a global economic recovery sent a wave of risk aversion across global markets Friday that continued Sunday when the Middle East opened for the week.

Moderna said in a release on Friday that it was working rapidly to test the current vaccine against the omicron variant, and studying two booster candidates.

"Since early 2021, Moderna has advanced a comprehensive strategy to anticipate new variants of concern," the company said. "The company has repeatedly demonstrated the ability to advance new candidates to clinical testing in 60 to 90 days."