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CDC hunting for omicron variant in U.S. as cases spread globally

80,000 Covid samples are being tested every week to find the new variant, the agency's director said Tuesday.

The Centers for Disease Control and Prevention said Tuesday that it has drastically increased its ability to test SARS-CoV-2 virus samples for the omicron variant.

The agency said it's now sequencing about 1 out of every 7 PCR tests positive for Covid-19, which is approximately 80,000 samples per week.

“That’s more than any other country,” CDC Director Dr. Rochelle Walensky said during a White House Covid briefing Tuesday. Earlier this year, she said, the CDC was sequencing about 8,000 samples per week.

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By far, the highly contagious delta variant continues to be most dominant, accounting for 99.9 percent of Covid cases in the United States, according to CDC data.

This scanning electron microscope image shows SARS-CoV-2 (orange) also known as 2019-nCoV, the virus that causes Covid-19.
A scanning electron microscope image of SARS-CoV-2, in orange, the virus that causes Covid-19. NIAID-RML

The omicron variant has not yet been detected in this country, but experts say it's only a matter of time. Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, said that as of Tuesday afternoon, 226 cases had been found in 20 countries, including neighboring Canada.

"It might already be here, certainly not in large amounts, but it may already be here," he told MSNBC's Craig Melvin on Tuesday.

The Association of Public Health Laboratories is working with the CDC to analyze Covid-19 samples nationwide. During a media briefing Tuesday, Scott Becker, chief executive officer for the APHL said that he expects to find the variant "any day now."

"I’m not that much of a betting guy, but I bet it’s here really soon," Becker said, adding that it's probably just a question of how wide the variant has already traveled.

Once the variant is detected, the CDC is expected to make an announcement.

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Many questions about omicron remain: Does it spread faster than delta? Does it cause people to get sicker? How well do the vaccines protect people against the variant?

It will likely be several weeks before scientists can pin down those answers; any guesses before then "remain speculative," Fauci said during the Covid team briefing.

While there is preliminary evidence that omicron’s mutations may render the vaccines less effective, experts say they’re highly unlikely to render them useless.

Indeed, the Biden administration has strengthened its push for a Covid booster shot for all adults.

"Getting boosted will give you the highest level of protection from Covid and this new variant," White House Covid response coordinator Jeff Zients said during Tuesday's briefing.

Nearly 75 percent of those eligible for Covid vaccines have received at least one dose, according to CDC data. Just under 22 percent eligible for the booster have had the shot.

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