A senior Biden administration official has a grim warning as new data reveal that Omicron cases could surge in the U.S., with about 60 million Americans still unvaccinated.

“Everything points to a large wave. A large wave is coming," the senior Biden administration official, who was unnamed in the report, told Axios. “It will be fast. It won't be as severe, but regrettably, there will be plenty of hospitalizations.”

The comments from the senior official come after a new analysis of South Africa COVID cases by Discovery Health, the largest private insurer in the country.

The data found that two doses of Pfizer’s COVID vaccine provided significantly less protection against severe disease with Omicron than previous variants, but is less likely to lead to hospitalizations.

The analysis found that the vaccine’s two-dose regimen was 70% effective against severe disease and only 33% effective against infection from Omicron.

The Omicron variant of COVID-19 was first detected in South Africa last month and deemed a “variant of concern” by the World Health Organization on Nov. 26.

If the U.S. mirrors the Omicron situation that is playing out in Europe, it could see cases of the variant spreading rapidly, where they are doubling every two to three days.

The U.K. reported its first death from Omicron on Monday, where it is experiencing a “tidal wave” of COVID infections.

According to Scripps Research’s Eric Topol, who wrote on Substack on Monday, the Omicron’s exponential rise could take us to levels of 1 million cases per day in the U.S., which would have been considered an unthinkable projection.

However, there is still many unknowns about the Omicron strain, and scientists are scrambling to understand the variant’s transmissibility and severity as quickly as possible.

"Frankly, we don't have enough reliable, robust data at this point to give a clear direction as to what this will look like in the weeks to months ahead,” Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told Axios.

The nation’s leading infectious disease expert Dr. Anthony Fauci told CNN that preliminary data has been “a bit encouraging,” maintaining that it is “too early to make any definitive statement about it.”

Drugmakers Pfizer and Moderna have said that reformulated COVID vaccines that would protect against Omicron could be released as soon as early 2022.

Medical staff take care of a patient in the Covid-19 intensive care unit of the Robert Bosch hospital in Stuttgart
Medical staff takes care of a patient in the COVID-19 intensive care unit in the Robert Bosch Hospital in Stuttgart. AFP / THOMAS KIENZLE