Women in Bangalore, India, make red ribbons at an HIV support center in November 2012. Manjunath Kiran/AFP/Getty Images hide caption

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Refugees fill cans with water inside a camp in Baalbek, Lebanon, for Syrians who have fled the fighting in their country. Spencer Platt/Getty Images hide caption

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Health workers vaccinate a boy against polio at a May immunization drive in Mogadishu, Somalia. Farah Abdi Warsameh/AP hide caption

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Saudi men walk to the King Fahad hospital in the city of Hofuf on Sunday. In eastern Saudi Arabia, where outbreaks of the MERS virus have been concentrated, people have resumed their habits of shaking hands and kissing. Fayez Nureldine/AFP/Getty Images hide caption

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Two women in Colombo, Sri Lanka, attend a March protest calling for government action against domestic violence and rape. Dinuka Liyanawatte/Reuters /Landov hide caption

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A woodcut from the 1800s, Healing the Lepers, depicts the common tableau of Jesus healing a leper as his disciples look on. Images from the History of Medicine hide caption

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Boys at the L'Ecole Les Freres Clement elementary school in Jacmel, Haiti, line up to take deworming pills that protect against elephantiasis. Maggie Steber for The Washington Post/Getty Images hide caption

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A public health poster from 1952 encourages Americans to get checked for sexually transmitted diseases. Gonorrhea is the second-most-common sexually transmitted disease in the U.S., with more than 300,000 cases reported in 2011. Images from the History of Medicine hide caption

itoggle caption Images from the History of Medicine

Men outside a hospital in Dammam, Saudi Arabia, wear surgical masks as a precaution against infection with a coronavirus. Stringer/Reuters /Landov hide caption

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Students paste red ribbons on a window to mark World AIDS Day in Nanjing, China, in 2006. Although many infectious diseases have declined in the country, the number of new HIV cases nearly quadrupled between 2007 and 2011. AP hide caption

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A vendor weighs a live chicken at the Kowloon City Market in Hong Kong last April. After closing live poultry shops in many cities around China, the rate of new H7N9 infections sharply declined. Lam Yik Fei/Getty Images hide caption

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Oxana and Pavel Rucsineanu walk to the tuberculosis hospital in Balti, Moldova. Oxana and their new baby live in an apartment, but Pavel still has to stay at the TB ward, fighting for his life. Jason Beaubien/NPR hide caption

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Here's the coronavirus that appears to have originated in the Middle East and has caused severe illnesses in people living there and in Europe. AP hide caption

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