Programs Help Reduce HIV Rates in Parts of Africa, Report Says

Virus Resurges in Uganda, Thailand

Seven African countries are experiencing a decline in the prevalence of HIV infection among young, urban adults, finally reaping the benefit of AIDS prevention and treatment, the United Nations said yesterday in its annual report on the global epidemic.

That good news was offset by troubling signs that the first African country to reverse the epidemic, Uganda, is experiencing a resurgence of infection, as is Thailand, another early success story.

Based on hundreds of national and regional surveys, the report stitches a patchwork of progress and setbacks: a successful national treatment program in Brazil and a new, aggressive response by the Chinese government, alongside a worsening HIV epidemic in the former Soviet bloc and a new outbreak among gay men in Europe.

But the pendulum swing underway in Uganda and Thailand appears to mark a new phase in the 25-year-old AIDS epidemic.

"It should not be a surprise that the countries first to show success will be the first to have a rebound and show problems," said Peter Piot, director of UNAIDS, the program run by the United Nations and the World Bank. "It is something that I am really very worried about."

He and other epidemiologists are trying to learn whether the resurgence of infection in the two nations is a demographic copy of the first wave of AIDS cases or represents the spread of infection to new groups. They are also trying to understand how big a part "prevention fatigue" may be playing in the trend.

"We really don't have an idea why it is happening," Piot said.

The findings make clear that vulnerable populations may differ somewhat from country to country, and that entire nations may be at different stages in the epidemic.

"One of the main messages is the need of countries to know their epidemic," said Paul De Lay, director of monitoring and evaluation at UNAIDS. "The epidemics are continuing to evolve."

Worldwide, 39.5 million people are infected by HIV, up 2.6 million from two years ago. This year, an estimated 4.3 million people will become infected and 2.9 million will die, according to the report. Two-thirds of all adults and children with HIV live in sub-Saharan Africa.

In many countries, HIV incidence is uncertain. Estimates based on the infection rate of pregnant women at public clinics are unrealistically high, and estimates based on household surveys (which often miss such high-risk people as commercial sex workers, drug users, soldiers and migrants) are deceptively low.

Most estimates now combine the methods, and although they are generally lower than previously cited rates, they are still shockingly high for many countries. In Zimbabwe, for example, 20 percent of people 15 to 49 are thought to be infected with the AIDS virus.