The United Kingdom reported the world's first known death from COVID-19 caused by the omicron variant as it quickly spreads throughout Europe
Health authorities say omicron cases are doubling every two to three days in Britain, and will replace delta as the dominant strain within days.
The variant has also been detected in more than half of U.S. states as health officials continue the push for Americans to get vaccinated and get booster doses.
So far, the original vaccines have offered at least some protection against variants. Even if immunity against omicron isn’t as good, Dr. Anthony Fauci, the country's top infectious disease expert, hopes the big antibody jump triggered by booster doses will compensate.
The variant was first identified in South Africa, where it's quickly becoming the dominant strain, and was designated as a "variant of concern" by the World Health Organization.
Here’s everything to know about omicron and why Americans should take notice.
What is omicron?
The World Health Organization designated the B.1.1.529 variant a “variant of concern” Nov. 26 and named it omicron after the 15th letter of the Greek alphabet.
WHO uses the Greek alphabet as a variant classification system to simplify understanding and avoid stigmatizing countries where they’re first identified.
Omicron, which can be pronounced both ä-mə-ˌkrän or ō-ˈmī-(ˌ)krän, according to Merriam-Webster, was first identified in South Africa on Nov. 24. The U.S. began restricting travel from South Africa and several other countries last week but Fauci said the Biden administration is considering lifting those bans.
“Hopefully we’ll be able to lift that ban in a quite reasonable period of time,” he said. “We all feel very badly about the hardship that has been put on not only on South Africa but the other African countries.”
What are the symptoms?
WHO says there’s no evidence to suggest that symptoms linked to omicron are different from those caused by other variants.
Dr. Angelique Coetzee, a private practitioner and chair of South African Medical Association, was one of the first doctors in South Africa to detect the new variant.
She told Reuters symptoms of the omicron variant were "very mild" and could be treated at home. These infections were first reported in university students who were younger and tended to have milder disease.
But like all coronavirus variants, WHO said, omicron may be capable of causing severe disease or death, particularly among vulnerable populations.
Symptoms of COVID-19 caused by any known coronavirus variant can include fever or chills, cough, shortness of breath, fatigue, muscle or body aches, headache, sore throat, a loss of taste or smell, sore and congestion or runny nose.
How serious is omicron? It will take weeks to understand new COVID-19 variant, experts say.
Where is first case of omicron in the United States?
A person in California became the first in the U.S. to have an identified case of the omicron variant.
“This is the first case of COVID-19 caused by the omicron variant detected in the United States,” Fauci said at the White House. He said the person was a traveler who returned from South Africa on Nov. 22 and tested positive on Nov. 29.
Where else has it been detected?
The CDC says the new variant has now been detected in 27 states: Arizona, California, Colorado, Connecticut, Florida, Georgia, Hawaii, Illinois, Iowa, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Texas, Utah, Virginia, Washington and Wisconsin.
The World Health Organization said last week the latest strain has been detected in at least 57 countries. Five countries in Africa accounted for 86% of the cases reported over the past week, according to WHO, but health officials still oppose travel bans targeting the continent.
“With omicron now present in nearly 60 countries globally, travel bans that mainly target African countries are hard to justify,” said Dr Matshidiso Moeti, the WHO regional director for Africa.
Should I be concerned about it?
In a media briefing last week, President Joe Biden said omicron is “a cause for concern, not a cause for panic.”
It’s not clear whether infection with omicron causes more severe disease compared to infections with other variants, WHO said.
It’s also unclear how well the virus evades immunity from previous infection or COVID-19 vaccines to cause a breakthrough infection.
But even with so little information, health experts say people should be watchful.
“Americans should take this variant seriously," Swann said. "Even if this one turns out to be not as bad as we fear, there will be another one that will.”
President Biden: Omicron 'a cause for concern, not a cause for panic'
Are there any deaths linked to omicron?
U.K. Prime Minister Boris Johnson on Monday reported the first known death from the omicron variant after saying the country faces a "tidal wave" of omicron cases.
The news comes after Johnson said Sunday he was opening booster shots to all adults. "I’m afraid it is now clear that two doses of vaccine are simply not enough to give the level of protection we all need," he said.
About 10 people are in U.K. hospitals with COVID-19 caused by omicron.
What makes omicron different from other variants?
Omicron appears to have about 30 mutations in on the coronavirus’ spike protein.
Out of the approximately 30 mutations, 26 are unique to omicron and don’t appear in other variants of concern, according to Dr. Venky Soundararajan, co-founder and chief medical officer at nference, a data analytics firm in Massachusetts.
In comparison, the alpha variant has only four unique mutations, beta has six, gamma has eight and delta has seven.
“I’m less concerned about the fact that these mutations exist and I’m more concerned about the fact that we know very little about many of them,” Soundararajan said.
A handful of omicron’s mutations that exist in other variants have been associated with previous surges of positive COVID-19 cases, he said. Some of these mutations are believed to increase transmissibility while others may help the virus evade immunity.
Most of these mutations are clustered at the ACE2 receptor and antibody binding sites, Soundararajan said, which are also sites targeted by the COVID-19 vaccines and antibodies.
The most intriguing mutation is the ins214EPE insertion, he said. This addition introduces three new amino acids, corresponding to nine nucleotides, to the virus’s genetic profile.
However, that doesn’t necessarily mean the insertion is more dangerous. A preprint study, not yet peer-reviewed, authored by Soundararajan shows this same insertion is present in seasonal coronaviruses.
This could mean the virus transmits more easily, he said, but it could also mean it causes only mild or asymptomatic disease to evade detection.
“In evolution, when you see a virus pick up a trait, it loses something else. You may see higher transmission but lower odds of hospitalization,” Soundararajan said. “That might be the silver lining.”
How quickly could it spread?
Scientists say more data is needed to determine severity of illness, but real-world evidence suggests omicron may be highly transmissible.
Dutch health authorities said they detected more than 60 COVID-19 cases among 624 passengers who flew on two flights from South Africa to Amsterdam’s airport, Reuters reported, despite requiring a negative test or proof of vaccination.
“The filtration on planes are better, there tend to be mask requirements and most airline companies are requiring a negative test, so I would not have expected this level of positivity so quickly on that flight,” Swann said. “I found it a bit worrisome.”
Do the COVID-19 vaccines protect against omicron?
Preliminary data from BioNTech found a third dose of its COVID-19 vaccine with partner Pfizer appears to be as effective against omicron as two doses were against the original variant.
The same study showed that two doses may prevent severe disease, but aren't nearly as effective against omicron as they were against earlier variants.
"The first line of defense with two doses of vaccination might be compromised (by omicron), and three doses of vaccination are required to restore protection," Özlem Türeci, BioNTech's chief medical officer, said in a news conference last week.
COVID-19 vaccine developers with authorized shots in the U.S. – Pfizer-BioNTech, Moderna and Johnson & Johnson – have all pledged to reformulate their shots to protect against omicron “if needed,” which may include an omicron-specific booster.
“It is imperative that we are proactive as the virus evolves,” Stéphane Bancel, Chief Executive Officer of Moderna, said in a statement. “The mutations in the omicron variant are concerning and for several days, we have been moving as fast as possible to execute our strategy to address this variant.”
What precautions should I take?
Preliminary evidence suggests there may be an increased risk of reinfection with omicron compared to other variants of concern, according to WHO, but more information is needed.
Biden urged the public to get fully vaccinated, and if eligible, to get a COVID-19 booster as soon as possible. Waning immunity in people who received their first shots more than six months ago may put them at risk of breakthrough infection.
The CDC updated its guidance, recommending that all adults 18 and older should get a booster shot either six months after their initial Pfizer-BioNTech or Moderna vaccine series or two months after their initial J&J vaccine.
“If you are 18 years and over and got fully vaccinated before June 1, go get the booster shot today,” Biden said. “They’re free and available in 80,000 locations coast to coast. Do not wait.”
Anyone who gathered with non-household members over the holiday should consider getting tested for COVID-19, Swann said. She also urged anyone who has traveled away from their community to get tested.
“That would allow us to get a handle on things,” she said. “It will continue to spread but slow it down to give us time to know what this is and what does it mean, and be prepared for it.”
Americans should also consider wearing masks, regardless of vaccination status, especially around people with compromised immune systems who are more at risk of severe disease, hospitalization and death from COVID-19.
Biden also pushed parents to get their children vaccinated now that the Pfizer-BioNTech vaccine has been authorized for kids 5 to 11.
“Most of our children across America are not fully vaccinated, yet,” Swann said. “People who are not fully protected with the full recommended dosage of vaccines should take extra care in gathering with anyone outside their household.”
Contributing: Karen Weintraub, USA TODAY. Associated Press. Follow Adrianna Rodriguez on Twitter: @AdriannaUSAT.
Health and patient safety coverage at USA TODAY is made possible in part by a grant from the Masimo Foundation for Ethics, Innovation and Competition in Healthcare. The Masimo Foundation does not provide editorial input.
This article originally appeared on USA TODAY: Omicron variant symptoms: What we know after UK reports first death