The CDC has updated its pre-departure health screening requirements for international travelers who will be visiting the U.S.
Starting December 6, 2021, air travelers aged two and older, regardless of nationality or vaccination status, are required to show documentation of a negative viral test result taken within one day of the flight's departure to the United States before boarding. You must show your negative result to the airline before you board your flight. That includes all travelers – U.S. citizens and legal U.S. residents (green card holders) and foreign nationals (non-immigrants).
For the latest COVID-19 travel policies, visit the site here.