The Centers for Disease Control and Prevention says doctors should prescribe Truvada, a once-a-day pill for HIV, to help prevent infections in IV drug users. Jeff Chiu/AP hide caption

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An electron micrograph of HIV particles infecting a human T cell. French researchers say they've found 14 patients with so little HIV virus in their blood that the patients have gone into "long-term remission." National Institute of Allergy and Infectious Diseases hide caption

itoggle caption National Institute of Allergy and Infectious Diseases

By taking antiretroviral drugs during pregnancy, this Tanzanian mother lowered the risk of passing HIV to her daughter. Siegfried Modola/AFP/Getty Images hide caption

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HIV drugs not only can keep patients healthy but also can stop the sexual transmission of the virus. Here an HIV-positive mother picks up medications at a hospital outside Johannesburg, South Africa. Alexander Joe/AFP/Getty Images hide caption

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United Nations Aids Executive Director Michel Sibide hugs Secretary of State Hillary Clinton after they they presented the a road map for stopping HIV around the world. Jim Watson/AFP/Getty Images hide caption

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A young man places an oral swab into a solution to complete an HIV test during a free screening event in Washington, D.C. Brendan Smialowski/Getty Images hide caption

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Students paste red ribbons on a window to mark World AIDS Day in Nanjing, China, in 2006. Between 2007 and 2011, the number of newly diagnosed HIV cases in China has nearly quadrupled to 40,000. AP hide caption

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The Durban Children's hospital opened in 1931, as a facility for all races, but tensions during the apartheid era forced it to close in the 1980s. Courtesy of KwaZulu-Natal Children's Hospital hide caption

itoggle caption Courtesy of KwaZulu-Natal Children's Hospital

Nurse Irena Majola tests Justice Mlambo's blood for HIV at a roadside AIDS testing table in a suburb near Cape Town. Under the "test and treat" strategy, about 45 million South Africans would need to be screened for HIV each year. Rodger Bosch/AFP/Getty Images hide caption

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