▶ Watch Video: Health officials say Americans should stay vigilant as COVID cases rise, Omicron continues to spread

U.S. health officials are warning that COVID-19 cases are still on the rise as the surge, driven by the Omicron variant, prompts a wave of disruptions across the country. 

The average daily number of new cases is over 176,000 — the highest it’s been in nearly a year, according to the Centers for Disease Control and Prevention. The spike is affecting everything from pediatric hospitalizations to college bowl games.

In New York, which is dealing with its worst coronavirus outbreak on record, state officials said pediatric hospitalizations quadrupled since early December. 

Schools are also making changes. Students at some major colleges and universities — like Columbia, Yale and the University of California, Los Angeles — will start next semester virtually. Others, like the University of Maryland and Northeastern, will resume in-person classes in January but recommend or mandate booster shots. 

The virus is even upending college football. The University of Miami withdrew from Friday’s Sun Bowl due to an outbreak on the team while two bowls scheduled for this week were canceled because of team withdrawals.

The surge comes as testing remains a major challenge across the country. Americans seeking a COVID-19 test over the Christmas weekend spent hours waiting in lines, with many unable to get tested.

COVID-19 cases among airline staff, pilots and crew led to a series of last-minute flight changes from Friday to Sunday, including more than 3,000 flight cancellations

Dr. Anthony Fauci on Sunday said while Omicron may cause less severe illness, Americans must not let their guards down. 

“Given the sheer volume of number of cases that you see now, every day, it goes up and up. The last weekly average was about 150,000, and it likely will go much higher,” President Biden’s chief medical advisor said.

“We’ve gotta be careful that we don’t get complacent about that because it might still lead to a lot of hospitalizations in the United States,” he said.

When asked about the nation’s testing infrastructure, Fauci admitted it needed improvement and that those improvements may not come until January, when the Biden administration plans to send up to 500 million at-home tests to anyone who wants one.