The following is excerpted from a bulletin posted by the U.S. Department of State, which is available online. A "frequently asked questions" page on the State Department's website addresses specifics of these updated requirements.

Please note: The federal government indicated on October 25 that more detailed written air travel requirements specifically for American mariners traveling to the U.S. from foreign nations would be available by now, but to our knowledge, these requirements have not yet been circulated.

"The Centers for Disease Control and Prevention (CDC) has announced a new Order for all air passengers traveling to the United States."

Effective November 8, 2021, "U.S. citizens and Legal Permanent Residents (LPRs) who are eligible to travel but are not fully vaccinated will need to provide proof of a negative COVID-19 test one (1) day before their flight's departure. U.S citizens and LPRs who are fully vaccinated will need to present airlines with proof of vaccination and of a negative COVID-19 test three (3) days before their flight."

For additional information, please visit the State Department's FAQ page for answers to questions about the requirement for proof of negative COVID-19 test or recovery from COVID-19 for all air passengers arriving in the United States.