Health experts track U.S. spread of Covid omicron subvariant

At least 22 states have detected a Covid-19 omicron subvariant, but health experts say it is not yet clear how dangerous it could be. Professor of Anesthesiology and Critical Care Medicine, Dr. Ebony Jade Hilton, joins News NOW to explain how the omicron subvariant differs from the original strain and whether the U.S. should be concerned about its spread.