Wencke Petersen, a Doctors Without Borders health worker, talks to a man through a chain link gate in September, when she was doing patient assessment at the front gate of an Ebola treatment unit. "There were days we couldn't take any patients at all," she tells NPR. Michel du Cille/The Washington Post hide caption

itoggle caption Michel du Cille/The Washington Post

A woman enters the Ebola treatment center at the Island Hospital outside of Monrovia, Liberia, Oct. 6. She said she was bleeding heavily from a miscarriage and was turned away from other clinics in the city. John Moore/Getty Images hide caption

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Medical workers will test the effectiveness of three new potential Ebola therapies at clinics run by the nongovernmental organization Medecins Sans Frontieres (Doctors Without Borders). Zoom Dosso/AFP/Getty Images hide caption

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Mariama and Fomba Kanneh play in an open space in Barkedu, Liberia. With schools closed across the country, many kids spend their time playing outside every day. Tommy Trenchard for NPR hide caption

itoggle caption Tommy Trenchard for NPR

Siatta Scott Johnson (at right), who has guided NPR journalists through Liberia and its lingo, advises two girls on how best to carry bananas and bread. Michaeleen Doucleff/NPR hide caption

itoggle caption Michaeleen Doucleff/NPR

Health workers sit at the emergency entrance of a Doctors Without Borders clinic in Monrovia. New data seem to show a decline in Ebola cases in Liberia, WHO says. Zoom Dosso/AFP/Getty Images hide caption

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Air Force personnel put up tents to house a 25-bed, U.S.-built hospital for Liberian health workers sick with Ebola in Monrovia, Liberia's capital. The hospital is scheduled to open this weekend. John Moore/Getty Images hide caption

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A burial team carries the body of woman suspected to have died from the Ebola virus in Monrovia, Liberia. Most of the organized burial teams in the country are assisted by the aid group Global Communities, which, among other things, trains workers to properly wear personal protective equipment, like the gear this team is wearing. Abbas Dulleh/AP hide caption

itoggle caption Abbas Dulleh/AP

Children play in the West Point neighborhood of Monrovia last week. West Point has been hit hard by Ebola. So local leaders formed their own Ebola task force, which goes door to door looking for cases. John Moore/Getty Images hide caption

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An Ebola health alert is displayed at the entrance to Bellevue Hospital in New York City, where Dr. Craig Spencer was quarantined after showing symptoms consistent with the virus. Bryan Thomas/Getty Images hide caption

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The nursing staff get a break at the Ebola care center run by Doctors Without Borders in Foya, Liberia. The center has helped stop the spread of the virus. Michealeen Doucleff/NPR hide caption

itoggle caption Michealeen Doucleff/NPR

New York Gov. Andrew Cuomo, left, listens Friday as New Jersey Gov. Chris Christie talks at a news conference in New York. The governors announced a mandatory quarantine for people returning to the United States through airports in New York and New Jersey who are deemed to be at "high risk" for Ebola. Mark Lennihan/AP hide caption

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Data sources: David Ropeik/Harvard University, National Weather Service, World Health Organization, Northeastern University Laboratory for the Modeling of Biological and Socio-Technical Systems, National Geographic, United States Census Adam Cole and Ryan Kellman/NPR hide caption

itoggle caption Adam Cole and Ryan Kellman/NPR

Amber Vinson in a photograph taken earlier this week at Emory University Hospital in Atlanta. Officials at Emory and the Centers for Disease Control and Prevention couldn't detect Ebola in Amber Vinson as of Tuesday evening, her family said in a statement. AP hide caption

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The Rev. Herman Browne voluntarily quarantined himself for 21 days after his wife's friend tested positive for Ebola. On Sunday, he returned to his church, Trinity Cathedral, to preach to his congregation about Ebola prevention. Jon Hamilton/NPR hide caption

itoggle caption Jon Hamilton/NPR

Thomas Eric Duncan, the first Ebola patient diagnosed in the U.S., at a wedding in Ghana. Texas Health Presbyterian Hospital Dallas, where Duncan was being treated for the disease, on Wednesday, Oct. 8, 2014 said Duncan has died. Wilmot Chayee/AP hide caption

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