The nurse, Kaci Hickox, who had no symptoms when she landed at Newark Liberty International Airport but developed a fever afterward, will have additional tests to confirm that finding, the New Jersey Health Department said in a statement. She was taken to University Hospital in Newark from the airport and will remain under mandatory quarantine for 21 days in accordance with a new policy announced late Friday afternoon by Gov. Andrew M. Cuomo of New York and Gov. Chris Christie of New Jersey.

A first-person account by Ms. Hickox of what happened to her when she landed in Newark was published on Saturday on the website of The Dallas Morning News. Ms. Hickox said that her fever registered 101 when it was taken with a forehead scanner by a "smug"-looking female officer at the airport. The reason, she said, was that her face was flush with anxiety over being detained with no reason given. When her temperature was taken later at the hospital with an oral thermometer, Ms. Hickox said on the website, it registered a normal 98.6.

The governors ordered quarantines for all people entering the country through Newark Liberty and Kennedy Airports if they had direct contact with Ebola patients in Guinea, Liberia and Sierra Leone, even if they showed no symptoms of infection upon arrival. The World Health Organization reported on Saturday that there are more than 10,000 suspected or confirmed cases in those three countries.