A new COVID variant dubbed omicron sparked global concerns and travel restrictions for several countries over the long Thanksgiving holiday weekend, but what makes it so troubling and what symptoms should you watch for?
The global risk of omicron is "very high," the World Health Organization said Monday, as more countries reported cases of the variant that has led to worldwide concern that there is more pandemic suffering ahead.
Here's a breakdown of what we know about the new omicron variant, its symptoms and where cases have been discovered so far:
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What makes omicron a variant of concern?
Despite the global alarm, there is still little understanding about the variant and how virulent it may be.
The World Health Organization announced last week that omicron has been classified as a "variant of concern."
WHO Health Emergencies Programme COVID-19 Technical Lead Dr. Maria Van Kerkhove said early evidence on omicron, known by the technical term B.1.1.529, shows that the variant has a large number of mutations, some of which have concerning characteristics.
Omicron has also shown to have an increased risk of reinfection compared to other highly transmissible variants, indicating that people who contracted COVID and recovered could be more subject to catching it again with this variant.
The leading infectious disease expert for the U.S., Dr. Anthony Fauci, added that public health experts are trying to find answers to questions such as whether the omicron variant causes more severe illness and whether it can evade protection from vaccines or treatments.
"It also has a bunch of mutations that would suggest it could evade the protection, for example, of monoclonal antibodies and perhaps even convalescent plasma for people who have been infected and recovered, and possibly vaccine. These are all maybes, but the suggestion is enough," Fauci said.
The quick spread of the variant is also concerning, he said.
"It seems to have really spread rather rapidly in South Africa, even though the numbers are relatively small, its ability to infect people who have recovered from infection and even people who have been vaccinated make us say, 'This is something you've got to pay really close attention to, and be prepared for something that's serious,'" Fauci explained. "It may not turn out that way, but you really want to be ahead of it, and that's the reason why we're doing what we're doing."
What are the symptoms of omicron?
COVID symptoms linked to the omicron variant have been described as "extremely mild" by the South African doctor who first raised the alarm over the new strain.
Dr. Angelique Coetzee, chair of the South African Medical Association, told the BBC on Sunday that she started to see patients around Nov.18 presenting with "unusual symptoms" that differed slightly to those associated with the delta variant, which is the most virulent strain of the virus to date and globally dominant.
"It actually started with a male patient who's around the age of 33 ... and he said to me that he's just [been] extremely tired for the past few days and he's got these body aches and pains with a bit of a headache," she told the BBC.
The patient didn't have a sore throat, she said, but more of a "scratchy throat" but no cough or loss of taste or smell — symptoms that have been associated with previous strains of the coronavirus.
Coetzee said she tested the male patient for COVID, and he was positive, as was his family, and then said she saw more patients that day presenting with the same kinds of symptoms that differed from the delta variant.
Other patients she had seen so far with the omicron variant had also experienced what she described as "extremely mild" symptoms, and she added that her colleagues had noted similar cases.
"What we are seeing clinically in South Africa — and remember I'm at the epicenter of this where I'm practicing — is extremely mild, for us [these are] mild cases. We haven't admitted anyone, I've spoken to other colleagues of mine and they give the same picture."
Where have cases been reported so far?
The extent of the actual spread of the omicron variant around the world, however, still remains unclear as countries discover new cases each day.
Scientists in several places — from Hong Kong to Europe to North America — have confirmed its presence.
The Dutch public health authority confirmed that 13 people who arrived from South Africa on Friday have so far tested positive for omicron. They were among 61 people who tested positive for the virus after arriving on the last two flights to Amsterdam’s Schiphol airport before a flight ban was implemented. They were immediately put into isolation, most at a nearby hotel.
Canada’s health minister says the country's first two cases of omicron were found in Ontario after two individuals who had recently traveled from Nigeria tested positive.
Authorities in Australia said two travelers who arrived in Sydney from Africa became the first in the country to test positive for the new variant. Arrivals from nine African countries are now required to quarantine in a hotel upon arrival. Two German states reported a total of three cases in returning travelers over the weekend.
A new surge was long anticipated and even a new variant, but the speed with which omicron hit came as a “shock” to South Africa’s health experts.
While numbers of confirmed cases are still relatively low, they have been increasing at a high rate. The new spike started after some student parties in Pretoria. Numbers quickly jumped from a few hundred cases a day to thousands. South Africa announced 3,220 new cases Saturday, of which 82% are in Gauteng province — home to Pretoria and South Africa's largest city of Johannesburg, according to the National Institute for Communicable Diseases. That's still well below the peak of the last wave, when more than 25,000 were confirmed in a day.
As many as 90% of the new cases in Gauteng province are caused by omicron, Tulio de Oliveira, director of the KwaZulu-Natal Research Innovation and Sequencing Platform, said in a tweet, citing the results of diagnostic tests.
Is omicron in the U.S. or Massachusetts?
The U.S. has yet to identify any cases but Fauci and other experts have warned that it could already have made it to America.
"I would not be surprised if it is. We have not detected it yet, but when you have a virus that is showing this degree of transmissibility and you're already having travel-related cases that they've noted in Israel and Belgium and other places, when you have a virus like this, it almost invariably is ultimately going to go essentially all over," Fauci said.
"I was actually reading about it in class and yeah, it's just very scary," said Talal Ammar, a student living in Boston.
Ammar's concerns stem from the unknown.
"My questions are like, how fast can it spread and how extreme is it, like how are the symptoms," he said.
Where is travel being restricted?
As cases of the variant are confirmed around the world, an increasing number of nations are tightening their borders despite pleas for caution and outbursts of dismay from some.
Effective Monday, the U.S. has restricted travel from South Africa and seven neighboring countries: Botswana, Zimbabwe, Namibia, Lesotho, Eswatini, Mozambique and Malawi.
Israel moved to ban entry by foreigners and mandate quarantine for all Israelis arriving from abroad.
And Japanese Prime Minister Fumio Kishida said Monday that Japan is considering stepping up border controls. Kishida told reporters that he planned to announce new measures in addition to the current 10-day quarantine requirement for travelers from South Africa and eight other nearby countries. Japan still has its border closed to foreign tourists from any country.
Morocco's Foreign Ministry tweeted Sunday that all incoming air travel to the North African country would be suspended to “preserve the achievements realized by Morocco in the fight against the pandemic, and to protect the health of citizens.” Morocco has been at the forefront of vaccinations in Africa, and kept its borders closed for months in 2020 because of the pandemic.
Many countries are introducing such bans, though they go against the advice of the WHO, which has warned against any overreaction before the variant is thoroughly studied.
What is Massachusetts doing about the new variant?
Gov. Charlie Baker told GBH News Sunday that he has been in touch with the White House and expects that more information on omicron and the threat it could pose will become available "relatively quickly."
"There are three big questions," Baker said. "The first is the transmissibility relative to previous variants. The second is the nature of the impact that it has on the people who get infected by it, which is a really important issue and a hard one for people to answer immediately. The third is, what's the likely issue associated with this relative to the vaccines that are already available? And that question, I think, will be answered relatively quickly."
The governor urged people who have not yet gotten vaccinated to do so and said people who have been vaccinated should get a booster shot as soon as they are eligible for one. Baker said he is planning to get his booster shot on Friday.
"Remember, we went through a similar exercise here on delta," he said during a separate interview on GBH's Boston Public Radio program Monday. "There was a lot of concern about transmissability and virulence. The conclusion was it was more transmissable, but not more virulent... The vaccines turned out to work quite well."
"I continue to believe the best thing people can do to protect themselves from any of these variants is get vaccinated if you're not and get a booster if you're eligible," Baker added. "I understand the concern, but I think people need to recognize and understand that people are chasing this pretty hard. You've got folks all over the globe who are chasing data and information and it'll probably take a few days to figure out what we don't know. But again, the best thing you can do is the stuff we've been preaching and practicing here in Massachusetts for a while."
Local doctors say the fact is that we just don't know enough about it yet to be sure of anything.
"We're going to be learning more about omicron, we're going to be learning more about how best to combat this, and so I think that's the first thing to remember -- that there's always going to be new evolutions," said Dr. Vandana Madhavan, a pediatric infectious disease specialist at MassGeneral Hospital for Children.
Instead of dwelling on what we don't know about this variant, we need to focus on the big picture, Marhavan said.
"The reason that we're seeing more variants is because, in other countries, the vaccination rate is so low," Madhavan said.
"What impact does it have on our vaccines? Because that is the most important tool we have to fight COVID-19," said Simone Wildes, a South Shore Hospital infectious disease physician.
"The virus will mutate, and the mutations will by chance sometimes make it more transmissible, less transmissible, and more virulent, maybe less virulent, maybe more immune evading, maybe less immune evading, and that's just chance," said Dr. Shira Doron with Tufts Medical Center.
While omicron does have a large number of mutations, that's not unexpected in a virus like this, Doron said: "It is likely that a triple vaccinated mRNA recipient will have very good, if not excellent, protection even against this variant, even if we find out that it's somewhat immune evading."
That's why these local doctors are continuing to encourage people to get vaccinated or boosted if they're eligible.
What about the rest of New England?
Maine Gov. Janet Mills issued a statement Monday saying she has directed the state's Department of Health and Human Services and the Center for Disease Control and Prevention to "closely track the new variant, particularly its severity, transmissability, and its potential impact on Maine people and our health care systems."
She said omicron has not yet been detected in Maine.
“The emergence of Omicron once again underscores the importance of taking commonsense steps like wearing masks when inside at public places, and, most importantly, getting vaccinated, including now getting your booster if you can," Mills added. "Vaccination remains the best and most effective way to protect your health and that of your loved ones, and we continue to strongly urge Maine people to get their shot, regardless of whether it’s your first or your third.”
Connecticut Gov. Ned Lamont had released a statement Sunday saying the state was monitoring for the new variant.
"Earlier this year we set up a network of labs, coordinated by the Connecticut Department of Public Health, that are conducting genomic sequencing on positive test specimens to provide understanding of the variants circulating in Connecticut. Our advance planning in this area will help us track Omicron, in addition to other variants that could appear in the future," Lamont said.
What are other states and countries doing about omicron?
In addition to travel bans, on Friday, New York Gov. Kathy Hochul declared a state of emergency amid a recent surge in coronavirus metrics and concern for potential spikes due to both the delta and omicron variants.
Going into effect on Friday, the order will allow New York to acquire pandemic-fighting supplies, increase hospital capacity and fight potential staffing shortages. It would also allow the state Health Department to limit non-essential and non-urgent procedures at hospitals.
In advice to its member states, the U.N. agency urged them to accelerate COVID-19 vaccination coverage "as rapidly as possible," particularly among high-priority groups, and to enhance surveillance and sequencing efforts.
Spain announced it won't admit unvaccinated British visitors starting Dec. 1. Italy was going through lists of airline passengers who arrived in the past two weeks. France is continuing to push vaccinations and booster shots.
What about vaccines and prevention of the new variant?
Moderna's Chief Medical Officer Paul Burton said Sunday the vaccine maker could roll out a reformulated vaccine against the omicron coronavirus variant early next year.
The vaccine maker "mobilized hundreds" of workers starting early Thursday morning, on Thanksgiving, to start studying the new variant, the company said in a statement.
Current vaccines could provide some protection, depending on how long ago a person was injected, Burton said. Still, he said unvaccinated people should get vaccinated or receive their booster shots, if eligible.
It's not clear whether new formulations will be needed, or if current COVID vaccinations will provide protection against the new variant that has begun to spread around the globe.
"We should know about the ability of the current vaccine to provide protection in the next couple of weeks, but the remarkable thing about the mRNA vaccines, Moderna platform is that we can move very fast," Burton said on BBC's "Andrew Marr Show."
"If we have to make a brand new vaccine I think that's going to be early 2022 before that's really going to be available in large quantities," the Moderna chief added.
According to Van Kerkhove, the WHO Technical Advisory Committee for Virus Evolution will be meeting "regularly" concerning the new variant.
She noted, however, that tests can take days and weeks to receive results that could provide a better understanding of the impacts with omicron.
Until more information is found, Van Kerkhove encouraged people to prevent their exposure to COVID infection by distancing, wearing a mask, avoiding crowded spaces, consistently washing hands and getting vaccinated.