US President Trump has appointed his Vice-President Mike Pence to coordinate the government response to the coronavirus outbreak.
Both men told a White House news conference that the risk to the American people remained very low.
The announcement came as new cases of Covid-19, the infection caused by the Wuhan coronavirus, continue to spread at a rapid pace around the world.
Sixty cases have so far been reported in the US.
Minutes after the White House news conference, the authorities confirmed another US case of Covid-19.
Addressing the press, Mr Trump expressed confidence that the US would be able to handle coronavirus.
"We're very, very ready for this," Mr Trump said. Researchers were "rapidly developing" a vaccine, he said.
The news conference came as Mr Trump was criticised for earlier suggesting in a tweet that the media had fanned unnecessary alarm over coronavirus "to make the Caronavirus [sic] look as bad as possible".
"USA in great shape!" he tweeted.
However, he admitted at his news conference that the US should prepare in case the virus spread. "Every aspect of our society should be prepared," he said.
He contradicted public health officials who earlier warned that spread of the virus to the US was a matter of when, not if. "I don't think it is inevitable," Mr Trump told reporters.
He credited decisions to limit certain flights into the US with containing the number of infections.