New Cases of HIV Decline in Africa for First Time

The number of people who became infected with the AIDS virus in sub-Saharan Africa decreased this year for the first time since the epidemic began three decades ago, according to a United Nations AIDS Program report released yesterday.

About 3.8 million people will become infected with the human immunodeficiency virus (HIV) in sub-Saharan Africa this year, compared with about 4 million last year, according to the report.

Officials of UNAIDS, a joint program run by the United Nations, the World Health Organization and the World Bank, don't know whether the slight decline marks a true turning point in the epidemic or a momentary pause. Nevertheless, the drop raises the possibility that the epidemic may be stabilizing in Africa.

"We have to interpret this with caution," said Peter Piot, executive director of UNAIDS, which is based in Geneva. "The least we can say is that the trend of an accelerating epidemic is now slowing down, and perhaps going down."

The report was greeted with similar caution--and optimism--by other experts.

"Knowing the built-in errors of the estimates, I would be reluctant to say the epidemic is starting to reverse. I think we can feel fairly safe in saying that it is leveling off, it is plateauing," said Paul De Lay, chief of the AIDS division at the U.S. Agency for International Development, the federal government's main foreign aid office.

"Yes, it's good news," said Debrework Zewdie, a physician with the World Bank's AIDS program. "But when we have done good surveillance in Nigeria, Ethiopia and South Africa, then I will be more confident."

Those countries have large populations, and small changes in their AIDS incidence can markedly change estimates for the entire continent. The margin of error of this year's overall estimate is about 200,000, so this year's incidence in Africa could be the same as last year's.

The stabilization--if true--is the result of many factors. One is the natural slowing of new cases when a disease "saturates" a susceptible population, as appears to be occurring in Botswana, where 36 percent of adults are infected. Successful prevention campaigns constitute another main factor.

Despite the possible drop, about 70 percent of the 36.1 million people infected with HIV worldwide are found in sub-Saharan Africa.

Globally, there were 5.3 million people newly infected with HIV this year, down slightly from 5.6 million last year. The number of people living with HIV and AIDS rose from 33.6 million last year to 36.1 million this year. The number of deaths rose from 2.6 million last year to 3 million this year.

Although the estimates of fewer new infections are encouraging, the total picture remains one of a global disaster far greater than was imagined even just a decade ago. The current number of HIV-infected people is more than double what the World Health Organization projected in 1991 for today.

In relative terms, the worst news of the year was the rise of infections in Eastern Europe and the former Soviet Union. The total number of people living with HIV in that region was 420,000 last year; now it is 700,000.

More than half of Russia's 300,000 infected people acquired the disease this year, according to UNAIDS estimates. There and in Eastern Europe, intravenous drug use is the virus's main mode of transmission, and men make up most of the victims.

"What we had predicted and feared is now happening, and that is an explosion of HIV," Piot said. "These figures are really alarming."

HIV prevalence varies widely, ranging from a high of 8.8 percent in sub-Saharan Africa to a low of 0.07 percent in East Asia (predominantly China).

The African estimates reflect three epidemics, De Lay said. The one in Uganda, Tanzania and other countries of the Great Lakes region has peaked and is declining, in part because of prevention programs and in part because it began more than 30 years ago. The second, in West Africa, has had a comparatively lower disease prevalence. The third, among southern African nations, is the most recent and has recorded high levels previously not thought possible.

"There continues to be a mosaic of epidemics in sub-Saharan Africa, and you can be lulled into a false sense of security if you look at the continent as a whole," De Lay said.

The greatest unanswered question in Africa at the moment, several experts said, is whether an epidemic similar to that in southern Africa will occur in Nigeria. Nigeria's HIV prevalence is about 5 percent.

In the United States, about 45,000 new infections occurred last year, a number unchanged over the past five years.

"In wealthy countries, AIDS is going down, mortality is going down, but there is a growing complacency," Piot said.

He added that he believes "the year 2000 has really been a turning point in the international response to the epidemic." He noted that Senegal, a relatively wealthy country with a low HIV prevalence, recently completed negotiations with several drug companies that will make three-drug combinations available to some of its citizens for between $950 to $1,800 a year, compared with more than $10,000 a year in the United States.