"I suspect within the [next few] months, Omicron will be the new virus in the world," Paul Kelly, the top medical advisor to the Australian government, told reporters.
His comments came after Australia reported its first case of community transmission even though it has closed its borders to high-risk southern Africa, one of a growing number of countries that have imposed travel restrictions to keep the variant out.
Global travel curbs accelerated on Thursday, with Hong Kong, the Netherlands, Norway and Russia, among others, announcing fresh measures to prevent the variant crossing their borders.
Such restrictions are wreaking havoc with the travel industry, pounding financial markets and undermining major economies just as they were beginning to recover from the lockdowns triggered by Delta.
Shares in Tokyo and South Korea fell on Friday after overnight losses on Wall Street, but traders will need to wait at least another week or so for answers from global health authorities on the variant's virulence or vaccine resistance.
Europe's biggest economy, Germany, said it would bar the unvaccinated from all but essential businesses, and legislation to make vaccination mandatory would be drafted for early next year.
Several countries including Britain and the United States were bringing forward plans to offer booster shots, but, like travel bans, this is controversial. Australian authorities said on Friday there was "no evidence" such moves would be effective.
U.S. Treasury Secretary Janet Yellen said that despite such uncertainty, the variant could slow global economic growth by exacerbating supply chain problems and depressing demand.
"There's a lot of uncertainty, but it could cause significant problems. We're still evaluating that," she told the Reuters Next conference on Thursday.
Biden on Thursday laid out his strategy to fight the coronavirus.
"We're going to fight this variant with science and speed, not chaos and confusion," he said, speaking at the National Institutes of Health medical research facility in Maryland.
Under Biden's plan, the United States will require inbound international passengers to be tested for COVID-19 within one day of departure, regardless of vaccination status. Mask requirements on airplanes, trains and public transportation vehicles will be extended to March 18.
The U.S. government will require private health insurers to reimburse their 150 million customers for 100% of the cost of over-the-counter, at-home COVID-19 tests, administration officials said, and make 50 million more tests available free through rural clinics and health centers for the uninsured.
New York has found five cases of the Omicron coronavirus variant, its governor said, becoming the fifth U.S. state to detect the variant and bringing the total number of infections in the country to nine.
The other U.S. states that have found Omicron cases are California, Colorado, Hawaii and Minnesota. In all four cases, the patients developed mild symptoms and all but one were fully vaccinated.
Less than 60% of the U.S. population, or 196 million people, have been fully vaccinated, one of the lowest rates among wealthy nations.
(Reporting by Reuters bureaux; Writing by Stephen Coates; Editing by Simon Cameron-Moore) ((email@example.com))