What to know about the omicron variant of the coronavirus

By Meryl Kornfield, Adela Suliman, Christine Armario, María Luisa Paúl and Lindsey Bever

Omicron has sparked alarm among epidemiologists worried that the new variant’s mutations could make it more transmissible. Scientists are racing to learn more as new cases are confirmed.

A new variant of the coronavirus, which causes covid-19, is raising concern around the globe.

Health authorities say the new variant, known by the Greek letter omicron, was first identified in southern Africa. Since then cases have since been confirmed in 20 countries as of Tuesday morning — though none has been detected in the United States.

In an address from the White House on Monday, President Biden said the variant is a “cause for concern, not a cause for panic.” He urged Americans to get the coronavirus vaccine and boosters, adding “we have more tools to fight the variant than we’ve ever had before.”

Omicron, which was listed as a “variant of concern” by the World Health Organization, was first reported in mid-November. Then South Africa confirmed last week that scientists had detected a variant with a high number of mutations that could make it more transmissible and adept at evading the body’s immune defenses — and released data on the new variant.

“This kind of transparency is to be encouraged and applauded because it increases our ability to respond quickly to any new threats,” Biden said.

Several countries, including the United States, have imposed travel restrictions from southern Africa while epidemiologists race to learn more. Many, but not all, cases have been tied to recent travel to Africa. In addition, U.S. health authorities are pushing vaccination as well as other mitigation measures such as masking, hand-washing and social distancing.

All of that said, there is too little research to draw conclusions. Anthony S. Fauci, the nation’s leading infectious-diseases expert, said Tuesday during a White House news conference that, at this time, “the effect of this variant on transmission, severity of disease and how well current vaccine treatments work remains speculative.”

Where has omicron been confirmed?

Omicron, pronounced aa-muh-kraan in American English, was first identified in southern Africa, but where it came from is unknown.

In South Africa, where nearly 25 percent of the adult population is fully vaccinated, the variant has spread rapidly. There were 50 new daily cases of coronavirus per 100,000 people in South Africa from Nov. 20 to 27, a 592 percent increase from the previous week, according to The Washington Post’s virus tracker.

Cases have also been identified in Australia, Belgium, Botswana, Britain, Canada, the Czech Republic, Denmark, Germany, Hong Kong, Israel and Italy. Dutch health authorities said Saturday that testing of about 600 passengers who arrived from South Africa found 61 infected with the virus, including 13 cases attributable to the omicron variant.

The U.S. Centers for Disease Control and Prevention said that omicron has not been detected in the United States, but officials are not resting easy. New York Gov. Kathy Hochul (D) declared a state of emergency Friday in response to a cold-weather surge of infections and the threat of the new variant. “It’s coming,” she said.

The WHO said on Sunday that the likelihood omicron will continue to spread “is high.”

“This is the most concerning variant we’ve seen since delta,” Eric Topol, director of the Scripps Research Translational Institute, said in an interview Nov. 26. “It’s going to take a really high bar for something to take over for delta, and we don’t know whether this is going to do it.”

What do we know about the new variant?

Omicron’s genetic profile is unique compared with other circulating variants, meaning it represents a new lineage of the virus.

It is distinct from other variants in another crucial way: There are a greater number of mutations. Tulio de Oliveira, director of the Center for Epidemic Response and Innovation in South Africa, said there are more than 30 mutations in the spike protein, the part of the virus that binds to human cells, allowing it to gain entry.

Scientists are worried that those mutations could make omicron more transmissible and potentially equipped to defy immune defenses, making vaccines less effective. The WHO said last week that preliminary evidence suggests an “increased risk of reinfection” compared with other variants.

“The one good news, if there’s any good news, is that this variant, the B. 1.1.529, can be detected by one particular PCR assay,” de Oliveira said at a news conference, meaning that diagnostic labs can quickly identify the new variant.

Jesse Bloom, a virologist at the Fred Hutchinson Cancer Research Center who has conducted mutational scanning experiments for the variant, noted that three mutations could make the virus a more elusive target for antibodies produced through vaccines or prior infection.

“What that’s going to mean for how likely people are to get infected, even if they’ve been vaccinated, it’s too early to say,” Bloom said, noting that more traditional experiments should provide more data. “But having a drop in the antibody neutralization is never a good thing.”

Linda Bauld, a professor of public health at the University of Edinburgh, said there were “genuine” reasons for concern, given that “it does look like a more transmissible variant.” But she added: “I think it’s premature to panic. … There’s just a lot we don’t know at the moment.”

Why is it called omicron?

The WHO named B. 1.1.529 omicron following the tradition of giving variants a Greek letter name.

After using the most recently named variant, mu, officials chose to skip the next letters available for variants, nu and xi.

“Nu is too easily confounded with ‘new,’ and Xi was not used because it is a common surname,” the WHO said in a statement to The Post. The agency’s “best practices for naming new diseases suggest avoiding ‘causing offense to any cultural, social, national, regional, professional or ethnic groups,’ ” the WHO noted.

What’s being done to halt the spread of omicron?

Public health authorities are urging individuals to get the coronavirus vaccine and, for those who are eligible, booster shots. The CDC on Monday expanded its recommendation on boosters for people 18 and older, stating that all adults “should” get a booster six months after the initial Pfizer or Moderna series or two months after the initial Johnson & Johnson vaccine.

In addition, Pfizer and its partner BioNTech plan to seek approval from the Food and Drug Administration for a booster shot for 16- and 17-year-olds, two people familiar with the situation told The Post.

The emergence of the omicron variant “further emphasizes the importance of vaccination, boosters, and prevention efforts needed to protect against COVID-19,” CDC Director Rochelle Walensky said in a statement.

“I strongly encourage the 47 million adults who are not yet vaccinated to get vaccinated as soon as possible and to vaccinate the children and teens in their families as well because strong immunity will likely prevent serious illness. I also want to encourage people to get a COVID-19 test if they are sick. Increased testing will help us identify Omicron quickly,” she said.

And Fauci said to continue taking other precautionary measures, such as wearing masks, practicing social distancing and avoiding crowds and poorly ventilated areas, washing hands frequently and, when needed, testing and isolating to protect others.

Within days of the discovery of the variant, several countries also began imposing restrictions on flights to and from South Africa and its neighbors.

Israel closed its borders to “foreigners from all countries.” Australia, Britain, Japan, Thailand and the United States are among nations curbing travel from southern Africa or imposing new quarantine rules for those arriving from the region. The United Kingdom said Saturday that it would require all international travelers to take a PCR test within two days of arrival and quarantine until their test returns a negative result.

The U.S. restrictions will apply to travelers from Botswana, Eswatini, Lesotho, Malawi, Mozambique, Namibia, South Africa and Zimbabwe. They do not apply to American citizens and lawful permanent residents. Biden saidin a statement that the move is “a precautionary measure.” He urged Americans to get vaccinated and get booster shots.

Officials in South Africa expressed concern about the travel bans, while some experts cast doubt on the efficacy of the restrictions, noting that they may be too late. The nation’s health minister, Joe Phaahlacharacterized them as a “draconian reaction.”

“It really doesn’t look scientific in any way,” he said. “That kind of reaction is quite a knee-jerk and panicked and almost wants to put a blame on other countries rather than work together.”

Before the novel coronavirus spread through the world, a study published in February 2020 in the Journal of Emergency Management found that a travel ban could delay the arrival of an infectious disease in a country by days or weeks. However, little evidence suggested that it eliminated the risk of the virus jumping borders in the long term.

Amesh Adalja, an infectious-disease physician and professor at Johns Hopkins University, said the measure would do little or nothing to curb the spread of a variant that may have been “spreading for probably several days or weeks before it was noticed.”

Faheem Younus, an infectious-disease specialist at the University of Maryland, said that by the time travel bans are imposed, “the new variant has already traveled out of the country.” He noted that the O.R. Tambo International Airport near Johannesburg serves more than 1 million travelers a month.

“These bans also come at a cost and will disincentive other countries in the future,” he said. “ ‘Why alert the world promptly if that means your people will be punished and your economy crushed?’ they might wonder.”

Do we know whether vaccines are effective against omicron?

Studies are underway to examine how vaccines will hold up against the new variant, with some experts expressing initial optimism that they will offer protection. Even if the variant limits the effectiveness of vaccines, it probably will not completely subvert the protections that vaccines provide, experts say.

“My expectation would be that the mutations in this variant are not going to ablate or completely escape that type of antibody neutralization” from vaccines or prior infection, said Bloom, the virologist.

“Regardless of whether or not this new variant ends up spreading, I would suggest that people do what they can to minimize their chances of getting infected with SARS-CoV-2,” Bloom added, referring to the virus by its technical name. “There are certain obvious things you can do: Get vaccinated, get a booster vaccination, wear a mask.”

Although the sample size is small, Ian Sanne, an infectious-disease specialist and member of South Africa’s Ministerial Advisory Council on covid-19, said physicians have seen a higher rate of breakthrough infections among those previously vaccinated in South Africa. Initial data indicates that vaccines are still effective, with the majority of hospitalizations being among those who hadn’t been immunized.

Fauci said Tuesday that with other variants, including delta, the vaccines and, particularly, boosters provide a level of protection, especially against severe disease. “So there’s every reason to believe, as we talk about boosters, when you get a level high enough that you are going to get at least some degree of cross protection, particularly against severe disease,” he said.

On Monday evening, Biden tweeted that the federal government would “accelerate” the development of omicron-resistant vaccines if necessary.

Meanwhile, vaccine makers, including Pfizer and its German partner BioNTech, Moderna, and Johnson & Johnson, said they are working to understand how well their vaccines can counter omicron.

In addition, Pfizer and BioNTech “expect to be able to develop and produce a tailor-made vaccine against that variant” within about 100 days, pending regulatory approval, a Pfizer spokesperson said in a statement.

And Moderna CEO Stéphane Bancel said in a news release that the company has been “moving as fast as possible to execute our strategy to address this variant,” also testing a booster to target this specific variant.

Given the spread of omicron in South Africa, several experts have pointed to the crucial need to vaccinate underserved countries to bolster the world’s protection from future, more-evasive variants.

“I think vaccine equity is a really important issue,” Bauld, with the University of Edinburgh, said, noting that the low vaccination rates in many African countries and the fact that high prevalence of the virus means it can undergo many genetic changes each time it jumps between individuals.

However, Bauld added, transmission of the coronavirus probably will not be eliminated even with a vaccine, as seen with the delta variant, with mutations ultimately able to “occur in any country.”

Will omicron cause severe illness, and will existing treatments work?

Because there are still a relatively small number of cases, it’s hard to know. While one physician in South Africa said initial patients had mild symptoms, another warned that she was seeing younger adults with moderate to severe disease.

“Making a general conclusion would probably be a mistake at this point,” Alex Sigal, a faculty member at the Africa Health Research Institute, told The Post. “But let’s say it doesn’t look hugely different from anything we’ve seen before.”

He added: “There’s no indication right now it’s going to do something completely different.”

Other experts point out that initial outbreaks appear concentrated in younger adults, many of whom would be less vulnerable to a severe infection. Richard Lessells, an infectious-disease expert in South Africa, noted on Twitter that there is also a time lag for infections to progress to severe disease and potentially result in hospitalization.

“We would only expect to see the impact on hospitalisations in the next few weeks,” he wrote.

Similarly, experts do not yet know how omicron might stand up to therapeutics developed to treat covid-19, including antivirals and monoclonal antibodies.

Bloom, the Fred Hutchinson Cancer Research Center virologist, said that because multiple mutations could combine in a way that dulls the impact of monoclonal antibody treatments, it’s difficult to assess which would be effective. But he said his experiments show initial indications that the Regeneron-Roche cocktail could “take a hit.”

Companies that have developed monoclonal antibodies say they are monitoring the variant.

How far might omicron have already spread?

Public health experts say there is a high probability that the new variant is already spreading in a number of countries beyond those where cases have been detected, noting that the first infection in Hong Kong involves a passenger who landed Nov. 11.

“That is two weeks ago, which is forever in the pace of a pandemic,” said Eric Feigl-Ding, a senior fellow with the Federation of American Scientists.

There are several other troubling signs. One of the first cases identified in Belgium, for example, involves a young woman who did not travel to sub-Saharan Africa. Health officials there said she developed symptoms 11 days after traveling to Egypt via Turkey. She had not been vaccinated and has not developed signs of severe disease.

Feigl-Ding also expressed concern at the large number of people who tested positive for the virus on two flights from South Africa that arrived in the Netherlands — about 10 percent of all passengers: “That’s quite a statistic, even if it’s not all omicron.”

Fauci told ABC News’s “This Week With George Stephanopoulos” that the variant’s arrival in the United States is essentially unavoidable.

“When you have a virus that has already gone to multiple countries, inevitably, it will be here. The question is: Will we be prepared for it?” he said.

Will omicron upend plans to return to ‘normal’?

After nearly two years into the pandemic, many are nervous about what challenges the new variant might bring and whether hard-fought gains will be lost. Public health experts are urging people not to jump to conclusions.

“I have never before experienced such an absolutely anguished outpouring as I have around this,” said William Hanage, an associate professor of epidemiology at the Harvard T.H. Chan School of Public Health. The response, he said, has “as much to do with humans as it does with the virus.”

Hanage said he is in a state of “weary alertness” waiting for more information. He suspects that omicron’s consequences will be more serious in some places than others, particularly those with low vaccination rates.

“This is certainly a curveball,” he said. “But exactly how serious it is remains to be seen.”

Stuart Ray, an infectious-disease specialist at Johns Hopkins University, said people should follow the “new wisdom” on the virus: keeping track of local infection rates to determine how vulnerable they are while using common-sense protection including vaccination, boosters, and high-quality masks such as KN95 and N95s.

“It’s still early days,” he said. “But this is probably not the last variant that we’ll see, so I think we should see this as part of the learning about this virus.”

Walensky, director of the CDC, said Tuesday during a White House news conference that one thing has become clear during the pandemic: “We cannot predict the future, but we can be prepared for it. And we have been doing exactly that — preparing for this moment.”

Source: The Washington Post

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