The recent announcement by South African scientists of a new COVID-19 variant has sparked fears across the globe, leading to a market sell-off and heightened anxiety about a pandemic entering its second winter.

The variant, currently referred to as B.1.1.529, was discovered in Botswana and has already been reported in South Africa, Belgium, Hong Kong, and Israel.

There have been numerous variants since the coronavirus first emerged, but the B.1.1.529 has drawn considerable attention because of how significantly it has mutated.

“What it has is a cluster of several mutations, more mutations than we’ve seen in that spike protein part of the coronavirus, and the spike protein is important because that’s what our vaccines target,” Amesh Adalja, senior scholar at the Johns Hopkins Center for Health Security, said on Yahoo Finance Live (video above). “That’s how the virus enters ourselves.”

Following the discovery, the World Health Organization (WHO) officially declared B.1.1.529 a "variant of concern" on Friday and later named the variant omicron.

“When we see mutations there, and there are some that are concerning, we worry: Is this more transmissible? Is this something that might be able to escape some of our vaccine protection? Is this something that might escape monoclonal antibody protection?” Adalja said. “All of these questions are going to be answered in the next couple of days or weeks, and that will allow us to fully characterize how much we should worry about this.”

The three dimensions

Dr. Lakshman Swamy, an ICU physician at Boston Medical Center, said that while there are reasons for concern, it’s not time to panic yet.

“There are three dimensions to this,” Swamy said on Yahoo Finance Live. “The first is: Is this variant going to spread more quickly, more like wildfire than Delta? Is it going to overtake Delta?”

He noted that “there’s a reason we’re all talking” about this current variant and that it should be closely examined to see how similar it is to the highly contagious Delta strain, which now accounts for almost all current COVID cases in the U.S.

The other two important questions to ask, Swamy said, are: Will it hurt and kill a lot of people? And will current vaccines work against it?

“I think we have nowhere near the numbers to know that right now,” Swamy said, but added that concerns over the effectiveness of the vaccines are valid. “There’s reason to worry because of the new mutations in the spike protein… but there’s no reason to assume our vaccines won’t offer significant protection there.”

The important caveat, though, is making sure everyone is vaccinated. Currently, 59.1% of those eligible in the U.S. are fully vaccinated while 69.7% have received at least one dose, as of Nov. 24. And, all three vaccines available in the country are now offering booster doses as a result of the Delta variant.

“The vaccine does a lot of things,” Adalja said. “It’s not just antibodies and it’s not just preventing mild illness. The goal is really to prevent severe illness. It’s a very high bar for any variant to be able to cause severe disease in a vaccinated person. So I don’t think we’re going to see a season as bad as last year because we really had nothing except for basic supportive care and remdesivir and dexamethasone. We’ve got so many more tools so I think that really protects us from having as bad of a winter. But it doesn’t mean it won’t be rough and that it won’t be hard. Hospitals may feel pressure, that’s probably inevitable.”

'Travel bans don't work

On Friday, the White House announced that the U.S. will begin restricting travel from South Africa, Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique, and Malawi starting on Monday.

Both Swamy and Adalja criticized travel bans, however.

“Travel bans don’t work,” Adalja said. “They end up stigmatizing a country. The countries that isolated this virus and reported it are now going to get penalized for being transparent. What is the implication for future variants if people get punished this way with travel restrictions? We have tests, we have tools, so it’s not as if we’re helpless the way we were back in January of 2020.”

Other countries have started implementing travel restrictions as a result of the new variant. Bahrain, Belgium, Britain, Croatia, France, Germany, Israel, Italy, Japan, Malta, the Netherlands, Hong Kong, the Philippines, and Singapore have all either halted or restricted flights from South Africa.

“I don’t think travel bans should be initiated or even be on the table,” Adalja said. “But unfortunately, it’s easy for politicians to put those into place because the general public will clamor for them, and it makes the politician look like they’re doing something when they actually make things worse.”

Swamy compared travel restrictions to “using a white picket fence to keep out mosquitoes.”

“It doesn’t make that much sense to me,” he said. “I think we’ve seen over the past year and a half, two years, that it really hasn’t made that much of a difference. I would love to see data that says that to the contrary but in my opinion, I don’t think these travel restrictions and travel bans really have that much of an impact on it. We’ve already seen it spreading.”

And, Adalja added, the variant has likely spread to even more countries that officials aren't yet aware of.

"So how do we counter that?" he said. "We counter that the same way we’ve been countering it all along. We get more people vaccinated and we stick to the same basic precautions. We don’t have to go to the extreme of quarantining and locking down everything if we can take precautions that are a little bit less than that earlier on.”

Adriana Belmonte is a reporter and editor covering politics and health care policy for Yahoo Finance. You can follow her on Twitter @adrianambells and reach her at [email protected].

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