Will flight restrictions help as new variant emerges?

A new coronavirus variant identified in South Africa is leading to a new round of travel restrictions just as many had finally begun to ease.

The risks of the variant, called omicron, are largely unknown.

But the World Health Organization has called it a “variant of concern” and governments around the world are not waiting for scientists to better understand the variant to impose flight bans and other travel restrictions.

On Friday, European Union nations agreed to impose a ban on travel from southern Africa to counter its spread. The 27-nation bloc acted within hours upon the advice of the E.U. executive, which said all countries needed to be extra cautious in dealing with the variant until it was clear how serious a threat the variant posed.

Johns Hopkins University infectious disease specialist Dr. Amesh Adalja said imposing restrictions makes politicians “look as if they’re doing something” but doesn’t make sense when countries now have countermeasures such as rapid tests and vaccines.

Sweden’s chief epidemiologist, Anders Tegnell told a local news agency said he does not believe that a travel ban would have any major effect, other than for countries with direct flights to the affected areas.

Stock markets plummeted around the world over worries about the variant — and reaction from political leaders.

“The most worrying thing about the new strain at the moment is how little we know about it,’’ said Craig Erlam, senior market analyst for the currency trading firm OANDA.