Pretoria- The deadly AIDS virus that is savaging South Africa is showing few signs of abating, government officials said Tuesday as they announced that half a million more South Africans were infected with HIV in the year 2000. The new statistics confirmed that this country remains the epicenter of the global AIDS epidemic with 4.7 million people infected with HIV, more than anywhere else on earth.

Twenty-five percent of adults - one of every nine South Africans - are now living with HIV. The number of people infected here last year outnumbered the entire population of the city of Atlanta. Government officials emphasized Tuesday that the disease was no longer spreading as rapidly as it did in the 1990s, when the percentage of HIV-infected adults jumped from less than 1 percent to more than 20 percent in less than eight years.

The officials said they were optimistic that the epidemic was finally reaching its peak. "The flattening of the curve over three years begins to suggest that the prevalence of HIV in the population may be stabilizing," said Manto Tshabalala-Msimang, the minister of health, at a news conference here Tuesday. But the statistics dashed the hopes of AIDS experts here and abroad, who said the increasing number of infections strongly suggested that the government's prevention programs were failing to dissuade thousands of young people from engaging in risky sexual behavior.

In 1999, 22.4 percent of South Africa's adults were infected by the AIDS virus, government statistics show. Last year, the figure was 24.5 percent. Health officials said the increase was driven by a spike in infections among young women in their 20s, who were seemingly untouched by or oblivious to the government's campaign to promote condoms, fidelity and abstinence.

And as the disease sweeps through urban townships and rural villages, it is threatening the aspirations of an entire generation that should be savoring this country's fledgling democracy. It has been only seven years since apartheid ended here. But if the epidemic continues to spread at its current pace, nearly half of the country's 15-year-olds will die of AIDS-related illnesses in coming years, United Nations officials said.

"I'm very shocked to hear these numbers," said Bernhard Schwartlander, a senior epidemiologist for the United Nations AIDS program, in a telephone interview from Geneva. "We knew the situation is bad, but clearly the numbers indicate that the epidemic is getting worse." "What worries me most is that we still have very high prevalence rates among the youngest groups, which indicates the programs have not reached extremely effective levels," Dr. Schwartlander said. "I know that the South African government is trying hard. But we have to be very clear that the leveling off that we have seen so far cannot be seen as a success."

In recent years, the South Africa government has been confounded by the disease, and officials have stumbled as they struggled to understand and control a disease of epic proportions. Last year, President Thabo Mbeki stirred an international furor by questioning the safety of commonly prescribed anti-AIDS drugs and the commonly accepted notion that the HIV virus causes AIDS.

Mr. Mbeki has withdrawn from that debate and his government has won praise from advocates for AIDS patients for its efforts to access low-cost anti-AIDS drugs. In recent weeks, the European Union and the World Health Organization have sided with South Africa, which is defending itself against a lawsuit filed by multinational drug companies.

The companies say the government's efforts to access generic drugs threaten existing patent rights. Nonetheless, several companies have lowered their drug prices in response to the mounting public pressure. But the statistics issued Tuesday, which were collected during the government's annual survey of HIV infection rates among pregnant women at public clinics, offered a grim reminder that the battle is far from won.