There are a lot of open questions about a new, highly mutated COVID variant, B.1.1.529, first detected in South Africa that is leading to travel restrictions across the globe. Some experts say there are causes for concern, but it also may not be a huge deal.

The World Health Organization (W.H.O.) has now named the variant Omicron, and on the advice of Dr. Anthony Fauci, President Joe Biden is imposing restrictions on travelers from South Africa and seven other African countries. Travelers will not be allowed into the United States starting Monday from Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique, or Malawi, in addition to South Africa — though U.S. citizens will be allowed to return with proof of a negative COVID test.

Designating it a "variant of concern," the W.H.O. put out a statement Friday saying, "Preliminary evidence suggests an increased risk of reinfection with this variant."

Tulio de Oliveira, the director of South Africa's Center for Epidemic Response and Innovation, said the variant has a "very unusual constellation of mutations" and "many more mutations than we have expected," per CNN. And de Oliveira added that Omicron "spreading very fast and we expect to see pressure in the health system [here] in the next few days and weeks."

It remains too early to say whether Omicron will prove more infectious than Delta, but the variant has 10 mutations on the protein associated with infecting human cells, which is far more than Delta. But the variant was discovered amid a sudden surge in new cases in South Africa, where, like in the U.S., cases had been dropping since the summertime Delta surge. Possibly driven by Omicron — though not necessarily — the surge has seen daily cases in South Africa quadruple since early November, to 850 per day, as the Telegraph reported earlier this week.

It also is not at all clear that Omicron is in any way more virulent or deadly than earlier variants. It should be noted that vaccinations have lagged in South Africa, and only about half the country has received one or more shots of a vaccine.

One case of Omicron has now been detected in Europe so far — a woman in Belgium who had been traveling abroad, but not in Africa. Other cases have now also been detected in Israel — at least four as of Friday afternoon — as well as in Hong Kong and Botswana.

Other experts remain skeptical that this variant should be cause for concern. Roberto Burioni, an Italian virologist, said today, "Substantively NOTHING is known about the new variant," and said that people should not be panicking.

As the New York Times reports, British Health Secretary Sajid Javid tweeted, "More data is needed but we’re taking precautions now."

Virologist Barry Schoub, the head of South Africa’s Ministerial Advisory Committee on COVID-19 vaccines, told a television station in Israel that he was not overly concerned in terms of the effectiveness of current vaccines against Omicron.

"I think what we can be pretty comfortable… that the vaccine will still prevent serious disease,” Schoub said, per the Times of Israel. “That I think we are pretty sure about. How effective it will be in preventing milder disease — that we’ve still got to understand."

Moderna put out a strategy statement Friday about addressing the latest variant, saying that it is testing multi-valent boosters for addressing new variants, in addition to higher doses of its existing booster.

"The combination of mutations [in Omicron] represents a significant potential risk to accelerate the waning of natural and vaccine-induced immunity," the company said in a release. "A booster dose of an authorized vaccine represents the only currently available strategy for boosting waning immunity."

"From the beginning, we have said that as we seek to defeat the pandemic, it is imperative that we are proactive as the virus evolves," said Stéphane Bancel, chief executive officer of Moderna, in a statement.

Top image: LONDON, ENGLAND - NOVEMBER 26: International passengers walk through the arrivals area at Terminal 5 at Heathrow Airport on November 26, 2021 in London, England. A heavily-mutated new variant of the Covid-19 virus, currently called B.1.1.529, has been detected in South Africa, Botswana and Hong Kong. The U.K. Health Secretary Sajid Javid said from 12:00 GMT on Friday all flights from South Africa, Namibia, Zimbabwe, Botswana, Lesotho and Eswatini are being suspended and the countries added to the UK's travel Red List. (Photo by Leon Neal/Getty Images)