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.