Health and Human Services Secretary Alex Azar announced on Friday that the coronavirus has been declared a public health emergency in the U.S. Beginning at 5 p.m. on Feb. 2, U.S. citizens returning from Hubei province will be subject to a 14-day quarantine, while other Americans who traveled elsewhere in China will be instructed to self-monitor for possible symptoms.

Azar also said that President Trump is temporarily suspending entry into the U.S. for foreign nationals who pose a risk of transmitting the virus.

In the same press conference, the Department of Homeland Security announced that starting on Sunday, flights coming to the U.S. from China will be funneled through seven airports that are equipped to screen passengers for symptoms of the virus.

The move comes as Delta Air Lines and American Airlines suspended flights between the U.S. and China, following several other international airlines who made similar announcements. United Airlines said that it was suspending flights to Beijing, Shanghai and Chengdu, but would continue flying to Hong Kong.