Two-thirds of the world's 40 million HIV/AIDS cases are in impoverished sub-Saharan Africa, which also has 12 million children orphaned by the disease. In the United States, the toll is heaviest on African-American women. Rich countries and private donors are now spending billions to fight AIDS in developing countries. But only 2 million people in those countries receive life-prolonging antiretroviral medications, while millions more are newly infected. With an HIV vaccine years away, public health experts say a renewed focus on prevention is the best way to stem the epidemic. Prevention turns on two stubborn issues: behavior change and shifts in generations-old patterns of poverty and gender inequality. Meanwhile, President Bush wants to reauthorize the President's Emergency Plan for AIDS Relief (PEPFAR) at $30 billion -- double current funding levels. While the program has pumped billions into overseas AIDS programs, AIDS groups want PEPFAR broadened to cover additional health and development issues.

Nellie Bristol is a veteran Capitol Hill reporter who has covered health policy in Washington for more than 20 years. She now writes for The Lancet, The British Medical Journal and the Journal of Disaster Medicine and Public Health Preparedness. She graduated in American studies from The George Washington University, where she is now working toward a master's degree in public health.