Story highlights U.S. restricts passenger arrivals from Liberia, Sierra Leone, Guinea to five airports

Spanish nurse's aide is free of the Ebola virus after another test, doctors say

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(CNN) The Spanish nurse's aide who contracted Ebola after treating virus-stricken patients in Madrid is now free of the virus, her doctors announced Tuesday after another test on her.

Teresa Romero Ramos is clear of Ebola, physicians at Carlos III hospital said.

She received an initial test, which turned up no virus in her blood, doctors said Sunday. More tests were administered to be sure she was virus-free.

While Spain welcomes the good news about Ebola, the United States is doing more to help prevent the spread of the virus. The Department of Homeland Security said Tuesday that all arriving passengers from West African countries that Ebola has hit hardest -- Liberia, Sierra Leone and Guinea -- must land in one of the five U.S. airports that have enhanced Ebola screening.

Those airports are New York's John F. Kennedy International; D.C.'s Washington Dulles; New Jersey's Newark Liberty International; Chicago's O'Hare International; and Hartsfield-Jackson International in Atlanta.

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