A Nigerian health commissioner Dr. Sani Malam vaccinates a child for polio during a national immunization drive in Bauchi, Nigeria, last week. Deji Yake/EPA /Landov hide caption

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A child is inoculated with the polio vaccine at a traffic checkpoint just outside Pakistan's capital, Islamabad. Roadside vaccinations help health workers reach children in mobile populations. Jackie Northam/NPR hide caption

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A health worker in Pakistan marks a child's finger with ink after giving him the polio vaccine. Jackie Northam/NPR hide caption

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Ado Ibrahim carries his son Aminu through a village in northern Nigeria. Aminu, 4, was paralyzed by polio in August. David Gilkey/NPR hide caption

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Health workers transport the polio vaccine by donkey in southeastern Pakistan. Asad Zaidi/Courtesy of UNICEF Pakistan. hide caption

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An Indian child receives the oral polio vaccine. Twice a year, an army of 2 million volunteers fans out across India to administer the vaccine. India has not reported a single case of polio in more than a year-and-a-half. Julie McCarthy/NPR hide caption

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With An Army Of Vaccinators, India Subdues Polio
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Children in a Lahore slum after heavy rains. The slum has a large population of Pashtuns who came from Pakistan's lawless tribal regions; many carry the polio virus with them. Jackie Northam/NPR hide caption

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How The Taliban Is Thwarting The War On Polio
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Sahya Idriss, a service provider at the health clinic in Minjibir, carries a vial of the polio vaccine. David Gilkey/NPR hide caption

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At Polio's Epicenter, Vaccinators Battle Chaos And Indifference
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During the peak of the polio epidemic in the U.S., some hospital wards even had large, room-like iron lungs where multiple children lived. Courtesy of Boston Children's Hospital Archive hide caption

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Wiping Out Polio: How The U.S. Snuffed Out A Killer
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A Pakistani man wheels Jamshid, an 8-year-old girl with polio, around the outskirts of the capital Islamabad last July. Behrouz Mehri/AFP/Getty Images hide caption

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An Indian boy receives a polio vaccination from an Indian health worker in Amritsar last year. Narinder Nanu/AFP/Getty Images hide caption

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India Marks A Year Free Of Polio
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Microsoft founder Bill Gates, his wife Melinda French Gates and British Prime Minister David Cameron at the World Economic Forum on January 28, 2011, in Davos, Switzerland. Johannes Eisele/AFP/Getty Images hide caption

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