WASHINGTON (AP) — Fending off demands to ban travel from Ebola-stricken West Africa, the Obama administration instead tightened the nation’s defenses against Ebola by requiring all arrivals from the disease-ravaged zone pass through one of five U.S. airports.The move responds to pressure from some Congress members and the public to impose a travel ban on the three countries at the heart of the Ebola outbreak, which has killed over 4,500 people, mostly in Liberia, Guinea and Sierra Leone, since it emerged 10 months ago.Beginning Wednesday, people whose trips began in Guinea, Liberia or Sierra Leone must fly into one of the five U.S. airports performing fever checks for Ebola, the Homeland Security Department said.Previously, the administration said screenings at those airports covered about 94 percent of fliers from the three countries but missed a few who landed elsewhere.There are no direct flights from those nations into the U.S; about 150 fliers per day arrive by various multi-leg routes.Homeland Security Secretary Jeh Johnson said “we currently have in place measures to identify and screen anyone at all land, sea and air ports of entry into the United States who we have reason to believe has been present in Liberia, Sierra Leone or Guinea in the preceding 21 days.”Since screening started Oct. 11 at New York’s Kennedy airport, 562 people have been checked at the five airports, according to Homeland Security. Of those, four who arrived at Washington’s Dulles airport were taken to a local hospital. No cases of Ebola have been discovered.The other airports are Newark’s Liberty, Chicago’s O’Hare and Atlanta’s Hartsfield-Jackson.Homeland Security officials at the airports use no-touch thermometers to check for fever, which can be a symptom of Ebola infection.