An artist on Rio de Janeiro's Copacabana beach puts the final touches on a sand sculpture of the assassin bug, which spreads Chagas disease. The sculpture was part of an event in 2009 commemorating the 100th anniversary of the discovery of the disease. Vanderlei Almeida/AFP/Getty Images hide caption

itoggle caption Vanderlei Almeida/AFP/Getty Images

Experiences in youth shape our health in old age. That's the key lesson from the world's longest-running medical study. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Public health innovation gets its closeup. Laila Abdul-Hadi Jadallah/FastForward Health hide caption

itoggle caption Laila Abdul-Hadi Jadallah/FastForward Health