Nurse Maria Vatista draws blood from a Greek drug addict for an HIV test in a mobile testing van in Athens last year. HIV infection rates are rising, as Greece's financial crisis has led the government to cut health and social services, including a successful needle exchange program. Yannis Behrakis/Reuters/Landov hide caption

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Timothy Ray Brown, shown in May 2011 with his dog Jack in San Francisco, is the only man ever known to have been fully cured from AIDS. Brown is known as the "Berlin patient" because he had a bone marrow transplant in a German hospital five years ago. Eric Risberg/AP hide caption

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A mobile clinic set up to test students for HIV is parked near Madwaleni High School in Mtubatuba, KwaZulu-Natal, South Africa on March 8, 2011. Parts of the South African province have HIV rates that are more than twice the national average. Stephane de Sakutin/AFP/Getty Images hide caption

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Activist Alexandra Volgina (right) accepts the Red Ribbon Award at the 19th International AIDS Conference for her grassroots group Patients in Control, which has worked to improve HIV treatment programs in Russia. Ryan Rayburn/IAS hide caption

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Health care workers in South Africa speak to residents during a door-to-door AIDS awareness campaign, part of a series of prevention efforts that has helped lower the country's HIV infection rate. Mujahid Safodien /Reuters /Landov hide caption

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Condom use has dropped among black youth, even as teens engage in less risky sexual behavior overall. Mike Segar/Reuters/Landov hide caption

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A heroin user keeps a syringe tucked behind his ear at a park in the city of Medan on Indonesia's Sumatra island. Cordita-Caritas Medan, a nongovernmental organization active there, works to reduce HIV infections through rehab of drug users and a needle exchange program. Sutanta Aditya/AFP/Getty Images hide caption

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Sir Elton John speaks Monday at the 19th International AIDS Conference in Washington. Carolyn Kaster/AP hide caption

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HIV patient Darnell Hollie, 47, talks to her doctor Monica Gandhi (right) at San Francisco General Hospital. Her path from drug addict to model patient was "a lot of work, but if you want it, it's there for you," Hollie says. Richard Knox/NPR hide caption

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Visitors view the AIDS Memorial Quilt at the National Mall in Washington, D.C., where the International AIDS Conference is being held this week. Ebony Bailey/NPR hide caption

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Anti-AIDS posters hang in the Eshowe public health clinic in South Africa's Kwazulu-Natal province. Clinicians there are hoping to slow the spread of HIV by getting more people treatment. Jason Beaubien /NPR hide caption

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Kim Gerlach of Vancouver waves the flag designed by Affirmative Aids Action for the XI International Conference on AIDS, July 1996. KIM STALLKNECHT/AFP/Getty Images hide caption

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HIV counselor Natrussa Williams explains the results of the oral HIV test to Katherine Tapp at the D.C. Department of Motor Vehicles in southeast Washington. There have been no babies born with HIV in the city since 2009, in part because of increased testing at locations including some high schools and the DMV. Jacquelyn Martin/AP hide caption

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