video thumbnail gupta orig explainer omicron
Dr. Sanjay Gupta explains how Omicron compares to other variants
03:50 - Source: CNN
CNN  — 

The US Centers for Disease Control and Prevention warns that the Omicron coronavirus variant could drive Covid-19 cases higher than ever before, according to modeling posted on the agency’s website this week.

“Current increases in Omicron cases are likely to lead to a national surge in the coming weeks with peak daily numbers of new infections that could exceed previous peaks,” CDC says.

Previously, cases peaked at their highest level in January 2021, with 7-day averages exceeding 250,000 new cases per day. Last week, the former director of the National Institutes of Health, Dr. Francis Collins, told CNN that “we might see hundreds of thousands of cases every day – maybe even a million cases in a day from Omicron.”

Experts say this doesn’t mean hospitalizations and deaths will rise at the same level we’ve seen with earlier surges, in part because the country has higher levels of immunity to Covid-19, and also because early data suggest Omicron may causes less severe disease.

Still, CDC notes that Omicron cases could still lead to “surges of hospital demand even if severity is reduced, because of the large number of anticipated cases occurring in a short period of time.”

CDC’s modeling looks at a number of scenarios by asking two key questions: How much more transmissible is Omicron versus Delta, and how well does Omicron evade the immunity we get through vaccination or prior infection?

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With low immune evasion, for example, peaks would be lower and occur several months later. But CDC says emerging case data “are consistent with the faster growth scenarios.”

“Upcoming holiday gatherings may further accelerate these trends,” CDC adds.

On Monday, CDC posted separate estimates that Omicron accounted for nearly three-quarters of cases last week.