The U.S. Department of Homeland Security (DHS) issued rules on Sunday to implement new restrictions on Americans who have recently visited China to address the threat of the coronavirus.

Airline officials said Sunday the new rules will mean they must now ask all U.S.-bound passengers if they have visited mainland China. Airlines are expected to scrutinize passports of travelers, and warned the new rules could require passengers to arrive even earlier for U.S.-bound flights.

American Airlines Inc. said Sunday it encouraged U.S.-bound passengers "to arrive at the airport three hours early as we expect this additional screening will lengthen the normal check-in process."