Jockeys take their camels home after racing in Egypt's El Arish desert. The annual race draws competitors from around the Middle East, including Saudi Arabia, where camels carry the Middle East Respiratory Syndrome virus. Nasser Nouri/Xinhua /Landov hide caption

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Sylvestre Mebam (right) runs an unauthorized health clinic in Cameroon's largest city of Douala. He and his assistant treat about 10 to 15 people each day. Andres Caballero/NPR hide caption

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New research finds a close connection between the flu that devastated the horse population in North America in the 1870s and the avian flu of that period. Hulton Archive/Getty Images hide caption

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Hannah Rood, 3, receives an H1N1 vaccine at a clinic in San Pablo, California, during the 2009 swine flu epidemic. Justin Sullivan/Getty Images hide caption

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A girl with hepatitis C holds a medical report while being treated at a hospital in Hefei, China, in 2011. China has one of the greatest burdens of hepatitis C, but it's still not clear whether a deal for lower prices for a new drug from Gilead Sciences will apply there. Barcroft Media/Landov hide caption

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Prostate cancer is the most common cancer for men in the West, while lung and liver cancers are the top problems in Asia. Courtesy of the World Health Organization hide caption

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A nurse attaches the low-cost breathing machine (far left) to an infant at The Queen Elizabeth Central Hospital in Blantyre, Malawi. Jocelyn Brown/Rice University hide caption

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Shoppers check out vodka in a street kiosk in Moscow in 2008. Alexander Nemenov/Getty Images hide caption

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Palestinian girls read the Koran at a camp in Gaza City, June 2012. In poor countries, boys are 20 percent more likely than girls to enroll in school, UNICEF says. Mahmud Hams/AFP/Getty Images hide caption

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Graduate student Jennifer Klunk of McMaster University examines a tooth used to decode the genome of the ancient plague. Courtesy of McMaster University hide caption

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A vendor sells chickens at the Kowloon City Market in Hong Kong last month. As a precautionary measure against the deadly H7N9 virus, Hong Kong has temporarily stopped importing poultry from mainland farms. Lam Yik Fei/Getty Images hide caption

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Young boys suspected of having Guinea worm infections wait for the parasite to emerge through the skin at a clinic in South Sudan. Louise Gubb/The Carter Center hide caption

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The U.K. has plenty of fresh produce available, such as these vegetables on display at a garden show in Southport, England. But these healthy options cost more in the U.K. than in any other country in Western Europe. Christopher Furlong/Getty Images hide caption

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