Early Reports on Omicron Variant Are Encouraging, Fauci Says

Carolyn Crist

December 06, 2021

Although the new Omicron variant is spreading across the U.S. and world quickly, early reports suggest that it may cause less severe disease than the Delta variant.

Doctors in South Africa, where the variant is becoming a dominant strain of the coronavirus, have said that hospitalization rates haven't yet increased dramatically.

"Thus far, it does not look like there's a great degree of severity to it," Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Diseases, told CNN's State of the Union on Sunday.

That said, scientists will need more time and information before drawing any definitive conclusions.

"But we have really got to be careful before we make any determinations that it is less severe or it really doesn't cause any severe illness, comparable to Delta," Fauci cautioned.

The Biden administration is deciding whether to lift the travel bans that started last week that bar people from entering the U.S. from several countries in southern Africa, Fauci said. Numerous countries have imposed travel restrictions to prevent the spread of the Omicron variant, which U.N. Secretary-General Antonio Guterres has called "travel apartheid."

"Hopefully we'll be able to lift that ban in a quite reasonable period of time," Fauci said. "We all feel very badly about the hardship that has been put on not only on South Africa but the other African countries."

Omicron Variant in the US

As of Monday morning, the Omicron variant had been detected in 17 states, according to The Washington Post. Georgia, Louisiana, Missouri, and Wisconsin were the latest states to confirm cases.

Average cases in the U.S. moved above 100,000 per day again during the weekend, and cases are likely to increase more.

"We are every day hearing about more and more probable cases," Rochelle Walensky, MD, director of the CDC, told ABC News's This Week on Sunday.

The Delta variant  remains the dominant strain of the coronavirus in the U.S., making up 99% of cases in the country and driving an increase in hospitalizations in northern states, she said. National Guard teams have been sent to help hospitals in western New York, and Massachusetts hospitals are limiting procedures that aren't urgent.

More than 6,800 new hospital admissions are being reported daily, according to CDC data. About 1,100 deaths are being reported each day.

The Omicron variant has dozens of mutations, which scientists are studying carefully, Walensky said.

"We know it has many mutations, more mutations than prior variants," she said. "Many of these mutations have been associated with more transmissible variants, with evasion of some of our therapeutics, and potentially evasion of some of our immunity, and that's what we're watching really carefully."

Looking ahead, Walensky said the course of the pandemic in the next 6 months depends on how people "mobilize together" to get vaccinated and follow COVID-19 safety precautions.

"We know from a vaccine standpoint that the more mutations a single variant has, the more immunity you really need to have in order to combat that variant," she said. "Which is why right now we're really pushing to get more people vaccinated and more people boosted to really boost that immunity in every single individual."

Omicron Variant Worldwide

In the shorter term, European officials have expressed concerns about the spike in Omicron cases in several countries as the holidays approach, according to The New York Times.

On Sunday, Britain and Demark confirmed  many new cases, suggesting that the variant has spread widely. Britain reported 246 cases -- nearly double the total on Friday. Denmark reported 183 cases, tripling the total from Friday.

Both countries are seen as leaders in genomic sequencing and testing, the newspaper reported, so they are finding cases because they are looking carefully for the new variant. Britain has focused testing on international travelers and close contacts of those who have received positive Omicron test results.

The Omicron variant has been detected in at least 50 countries worldwide, according to a map by the Times.

So far, British officials have told the public to proceed with their holiday plans and get booster shots.

"Our message is this: Enjoy Christmas this year. The vaccine rollout means we're in a position to do so," Dominic Raab, Britain's deputy prime minister, told the BBC on Sunday.

Even still, health officials in Denmark said they expect the Omicron variant to spread locally through community transmission. The variant has been detected among people who haven't traveled or had connections with travelers, the Times reported.

Other European countries have imposed restrictions to slow the spread of the variant in recent days, the newspaper reported. Belgium is requiring people to work from home and ordered schools to close a week earlier for Christmas. Italy has banned unvaccinated people from some leisure activities, and Ireland has closed nightclubs and restricted gatherings.

Germany, which has been hesitant to put strong mandates in place due to the country's history with authoritarianism, has banned unvaccinated people from numerous public activities and plans to require vaccination next year.

As the holidays approach, cases will likely continue to rise as people travel and gather in groups.

"We're going to see lots of big numbers over the course of the next several weeks in countries around the world," Michael Osterholm, PhD, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told the newspaper.

"And this shouldn't be a surprise," he said. "This virus is just acting like a highly transmissible respiratory virus."

Omicron Shares Genes With Common Cold Coronavirus

The Omicron variant may have picked up genetic code from another coronavirus that causes the common cold in humans, according to a new preprint study. The study hasn't yet been peer-reviewed or published in a journal.

The shared genetic material could mean that Omicron is more transmissible but causes less severe disease than other strains of the coronavirus, the study authors wrote.

Researchers from Nference, a Massachusetts-based company that analyzes biomedical information, sequenced Omicron and found a snippet of genetic code that is found in the HCoV-229E coronavirus, which can cause the common cold. This snippet hasn't been detected in other novel coronavirus variants so far, the authors said.

"By virtue of Omicron adopting this insertion…it is essentially taking a leaf out of the seasonal coronaviruses' page, which [explains]…how it lives and transmits more efficiently with human beings," Venky Soundararajan, PhD, one of the study authors and a biological engineer, told The Washington Post.

Researchers have found that SARS-CoV-2, which causes the disease known as COVID-19, can infect people who have also contracted other coronaviruses, the newspaper reported. Cells in the lungs and gastrointestinal tract can contain both viruses, which could allow one to share genetic material with the other, he said.

As a virus evolves to become more transmissible, it generally "loses" traits that cause severe disease, Soundararajan told the newspaper. But at the same time, scientists need more data to analyze the Omicron variant and know for sure what to expect in the months ahead, he said.


CNN Transcripts: "State of the Union," Dec. 5, 2021.

The Washington Post: "Omicron detected in 17 U.S. states and more cases likely, CDC says," "Omicron possibly more infectious because it shares genetic code with common cold coronavirus, study says."

ABC News: "Number of omicron cases in US ‘likely to rise,' CDC director says."

CDC: "New Admissions of Patients with Confirmed COVID-19."

The New York Times: "Spike in Omicron Variant Cases Puts Europe on Edge," "Tracking Omicron and Other Coronavirus Variants."

BBC: "Dominic Raab on Covid restrictions this winter."

OSF Preprints: "Omicron variant of SARS-CoV-2 harbors a unique insertion mutation of putative viral or human genomic origin."


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