Kwei Quartey sets one of the crime scenes in his second D.I. Dawson book in Agbogbloshie, an Accra slum. Ofeibea Quist-Arcton /NPR hide caption

itoggle caption Ofeibea Quist-Arcton /NPR

Barbara Bush helps a nun to fit on a hearing device during a 2012 event in Gulu, Uganda. She says was interested in architecture as a college student but became a global health activist after visiting East Africa with her parents. Reuters/Landov hide caption

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A member of the Lesotho military looks on as he stands guard in front of an armed personnel carrier at the entrance of the army barracks in the capital Maseru on Saturday. Lesotho's Prime Minister Thomas Thabane has accused the army of staging a coup. Siphiwe Sibeko/Reuters/Landov hide caption

itoggle caption Siphiwe Sibeko/Reuters/Landov

Peter Piot was one of the co-discoverers of the Ebola virus in 1976. "I never thought we would see such a devastating and vast epidemic," he says. Leon Neal/AFP/Getty Images hide caption

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The orchids that produce vanilla beans have no natural pollinators in Madagascar; the plant must be pollinated by hand — a labor-intensive process with little margin for error. Courtesy of Madécasse hide caption

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A team of body collectors carry the corpse of a woman suspected of dying of Ebola in Monrovia, Liberia's capital. Tommy Trenchard for NPR hide caption

itoggle caption Tommy Trenchard for NPR

Shops are closed in Monrovia's West Point neighborhood as part of a quarantine to contain the spread of Ebola. Zoom Dosso/AFP/Getty Images hide caption

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Islamist fighters in the Libya Dawn coalition guard the entrance of the Tripoli International Airport on Sunday. After days of battles, they captured it from forces aligned with rogue general Khalifa Hifter. Mahmud Turkia/AFP/Getty Images hide caption

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