"We never really turned back the epidemic," said Neff Walker, an epidemiologist at UNAIDS. "It just keeps going on." Walker and other experts worry about the spread of the disease through the huge population of China and about the rapidly rising infections in Southeast Asia and Eastern Europe. "Everyone feels like the worst is still to come," Walker said. In the Ukraine, an estimated 240,000 people had HIV in 1999. Up to 80 percent were drug users infected by dirty needles. Today, "the situation continues to worsen," said Nina Horehiliad of Ukraine's Center on AIDS.

In sub-Saharan Africa, home to 70 percent of the world's AIDS infections, hospitals are filled, cemeteries are packed with the bodies of 20- and 30-year olds, and grandparents are raising orphaned children. In most countries on the poorest continent, the infected have no hope of getting AIDS medications. "I don't think we know what we are dealing with because the knife is coming down, and it's a silent one," Jenny Marcus, coordinator of Community AIDS Response. "People are just quietly disappearing." In South Africa, where 4.7 million people are infected, AIDS has orphaned 420,000 children, thousands of whom are living in households headed by children.