Top U.S. infectious disease official Anthony Fauci said in an interview with NBC News on Sunday that the newly discovered COVID-19 variant Omicron is a "clarion call" for people to get vaccinated.

The U.S. hasn't detected cases related to Omicron but Fauci said it will inevitably hit the country. 

"As we all know, when you have a virus that has already gone to multiple countries, inevitably it will be here," he said in another interview with ABC News.