WILMINGTON, Del. (AP) The COVID-19 omicron variant is just raging around the world, the White Houses top medical adviser said Sunday as President Joe Biden prepares to issue a stark warning of what the winter will look like for unvaccinated Americans.

Dr. Anthony Fauci , the countrys leading infectious disease expert, told NBCs Meet the Press that the real problem for the U.S. hospital system is that we have so many people in this country who are eligible to be vaccinated who have not yet been vaccinated.

The prospect of a winter chilled by a wave of coronavirus infections is a severe reversal from the optimism projected by Biden some 10 months ago, when he suggested at a CNN town hall that the country would essentially be back to normal by this Christmas. Biden has been careful not to overpromise, yet confidence in the country has been battered by an unrelenting wave of COVID-19 mutations and variations that have left many Americans emotionally exhausted, dispirited and worried about infections.