Black mambas are one of the fastest snakes in the world and grow up to 14 feet long. But their venom is no match for the antidote Fav-Afrique. Balint Porneczi/Bloomberg/Getty Images hide caption

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A long legacy in global health: Former President Jimmy Carter has worked to end neglected diseases since 1982. Here he sits with former South African President Nelson Mandela at a ceremony in Soweto, celebrating a new AIDS project in 2002. AFP/Getty Images hide caption

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A celebration erupts in the streets of the Massessehbeh village on Friday, after President Ernest Bai Koroma officially ended Sierra Leone's largest remaining Ebola quarantine. Sunday Alamba/AP hide caption

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The PharmaChk is a bit like a litmus test for drugs: You pop in a pill at one end, and in 15 minutes, a number appears on a screen telling you the drug's potency. Mahafreen H. Mistry/NPR hide caption

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A woman receives the rVSV-ZEBOV Ebola vaccine at a clinical trial in Conakry, Guinea. The vaccine appears effective after only one shot. Cellou Binani/AFP/Getty Images hide caption

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Slum dwellers near Calcutta get their water from a municipal pipe. Water coming out of the tap on the left is for bathing and so is untreated. The blue Zimba chlorinator is hooked up to the tap on the right, which is used for drinking water. Courtesy of Suprio Das/Zimba hide caption

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A family receives treatment for cholera at a clinic run by Doctors Without Borders in Port-au-Prince, Haiti, in October 2011, a year after the overwhelming outbreak began. Ramon Espinosa/AP hide caption

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Russia has strict rules on dispensing painkillers. Family members say some cancer patients killed themselves because they could not obtain the medicine and the pain was too great. Andy Baker/Ikon Images/Getty Images hide caption

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Health workers wash their hands after taking a blood sample from a child to test for the Ebola virus. On Tuesday, the workers tested people in the village outside Monrovia where a 17-year-old boy died of the disease over the weekend. Abbas Dulleh /AP hide caption

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The outbreak of Middle East respiratory syndrome is slowing down in South Korea, but people were still wearing surgical masks around Seoul on Monday. Ed Jones/AFP/Getty Images hide caption

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A police officer guards the home of a family under a 21-day Ebola quarantine in Freetown, Sierra Leone, back in March. Michael Duff/AP hide caption

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In front of the emergency room at the Samsung Medical Center in Seoul, medical workers care for a man suspected of having the Middle Respiratory syndrome on Monday. Jung Yeon-Je/AFP/Getty Images hide caption

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Primal posture: Ubong tribesmen in Borneo (right) display the perfect J-shaped spines. A woman in Burkina Faso (left) holds her baby so that his spine stays straight. The center image shows the S-shaped spine drawn in a modern anatomy book (Fig. I) and the J-shaped spine (Fig. II) drawn in the 1897 anatomy book Traite d'Anatomie Humaine. Courtesy of Esther Gokhale and Ian Mackenzie/Nomads of the Dawn hide caption

itoggle caption Courtesy of Esther Gokhale and Ian Mackenzie/Nomads of the Dawn

Patient one: A businessman brought the Middle East respiratory syndrome to South Korea in early May. Since then, he has likely spread the virus to more than 20 other people. Several of those have passed the virus onto others. Maia Majumder/Health Map hide caption

itoggle caption Maia Majumder/Health Map