Coronavirus Live Updates: Scientists Race for a Cure as Death Toll Rises

United States health officials have announced expanded screening measures for passengers arriving from China at 20 ports of entry to the United States.

Expanded screening had previously been at only five airports; now, the Centers for Disease Control and Prevention said that all 20 of its quarantine stations in airports and land stations across the mainland United States are participating, as well as those in Alaska, Hawaii and Puerto Rico.

[A plane carrying Americans is leaving from Wuhan. If you know anyone on board, or anyone trying to leave Wuhan, we would like to hear from you for a coming article. Please contact Miriam Jordan at [email protected] to share your story.]

Americans are now discouraged from traveling to any part of China, and other travel restrictions have not been ruled out, officials said. Only five people in the United States are known to have been infected so far.

Officials also announced on Tuesday that Chinese authorities will allow teams of international experts, coordinated by the World Health Organization, to help with research and containment.

In the United Kingdom, the British Foreign Office is warning against all travel to Hubei Province and against all but essential travel to the rest of mainland China. (The warning does not include Hong Kong and Macau).

And the European Union — at the request of France, which has many citizens in the Wuhan area — announced that it was sending two flights to China to evacuate at least 350 healthy citizens of the bloc.

Reporting was contributed by Chris Buckley, Russell Goldman, Elaine Yu, Raymond Zhong, Alexandra Stevenson, Paul Mozur, Knvul Sheikh, Katie Thomas, James Gorman, Motoko Rich, Ben Dooley, Eimi Yamamitsu and Patricia Cohen. Jin Wu, Zoe Mou, Albee Zhang, Amber Wang, Yiwei Wang and Claire Fu contributed research.