Omicron is spreading 'every place at once,' experts say. What it could mean for holiday plans.

Some medical experts are starting to put the brakes on their holiday gatherings because of the omicron variant of COVID-19, which is moving faster than the systems can track.

"I'm rethinking my plans for the holidays, I'm the director of pathogen genomic surveillance at the Broad Institute of MIT and Harvard University," MacInnis said on the call. It's the responsible thing to do and what feels right.

She and a few other Massachusetts-based researchers on the call said they were shocked by the pace at which omicron has been taking over.

About 3% of current COVID-19 cases in the U.S. are omicron, according to the Centers for Disease Control and Prevention. The number is likely to be much higher now that the CDC has said it.

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There isn't a system on the planet that could keep up with it at the rate that it is spreading.

Jeremy Luban, a virus expert at the University of Massachusetts Medical School, said that in some parts of the country there are hints omicron already accounts for 15% of cases.

Jacob Lemieux, an infectious disease expert at Massachusetts General Hospital, said that Omicron has been moving faster than he thought it would. There is a high chance that it will come to your holiday gathering.

The variant is called the COVID-19 omicron.

Lemieux said that previous versions popped up in one country and then another, but that now it seems to be happening every place at once.

More than 5 million people have died from the COVID-19 virus, including over one million in the United States.

The variant was only identified the day before Thanksgiving, but as more data emerges, it's clear that omicron is twice as fast as delta, which has dominated the global pandemic since this summer.

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Lemieux said that even if omicron is less dangerous, it will still cause a large number of infections and deaths.

The U.S. was seeing a growing number of infections with the delta variant. There were an average of 118,000 new infections a day over the last week, a 37% increase over the previous week.

Hospitals are filling up. Lemieux said that staff are tired. There may be limits on capacity to handle the kind of caseloads that we see from an omicron wave superimposed on top of the delta surge, because we are almost two years into the pandemic.

The variant of omicron has been identified in South Africa. When delta reached its peak there, Omicron already had as many cases as it did.

A security guard stands in front of a ward at a hospital in India preparing for a coronaviruses variant.

Discovery Health, the largest private health insurer in South Africa, has found that vaccines and prior infections are less protective against omicron than they have been.

It is not clear if the variant is less dangerous or if it is because of the prior vaccinations and infections that patients are less likely to need to be resuscitated. MacInnis and the others spoke. About 16% of South Africans have been hospitalized.

The scientists on the Tuesday call said they were rethinking gathering for Christmas.

Dr. Amy Barczak is a professor of medicine at Harvard Medical School.

She said that her family had changed their plans so that they wouldn't be getting together with vulnerable members of the family during the holidays.

Senior citizens, people who are immune compromised and people who have other health conditions will remain the most vulnerable.

MacInnis said that it was not yet known how sensitive the tests are for the omicron variant, so it was not possible to mitigate some of the risk.

The first case of the omicron COVID-19 variant was found in San Francisco.

If a group is definitely getting together, at- home rapid tests could be useful, but Lemieux urged caution.

He thinks it's time to reexamine whether a gathering is necessary.

Lemieux said that if people go ahead with a gathering, they should "do everything you can to conduct it as safely as possible", which means staying outdoors as much as possible, opening windows and masking.

Luban and others said that flying is safe because of masking, vaccinations and good air quality. The experts on the call said that travel restrictions don't work because the virus has already spread.

Booster shots seem to restore protection that may have faded with time. Vaccines may be stopping the most severe cases in South Africa because fewer people are dying from omicron than before.

MacInnis said that the rise of omicron does not mean that our vaccines are failing us.

Karen Weintraub can be reached at

The Masimo Foundation for Ethics, Innovation and Competition in healthcare gave USA TODAY a grant to cover health and patient safety. Editorial input is not provided by the Masimo Foundation.

Some experts are worried about the variant, which is called 'Happening every place at once'.