According to a U.N. update published Monday, AIDS has killed more than 25 million people since it was first recognized in 1981, making it one of the most destructive epidemics in history. An estimated 3.1 million people died from the virus last year and another 4.9 million people became infected.
Last year, the total number of people living with the virus was estimated at 39.4 million.
UNAIDS chief Peter Piot says, for the first time, there is evidence that increased efforts to combat the disease over the last five years have led to fewer new infections in some places.
"Now we have Kenya, several of the Caribbean countries and Zimbabwe with a decline," Piot said, adding that Zimbabwe is the first place in Southern Africa, the hardest-hit area, to show improvement.
These are all countries that have invested heavily in safe-sex campaigns and other prevention programs.
"People are starting later with their first sexual intercourse, they are having fewer partners, there's more condom use," Piot said.
The most dramatic drops have been among pregnant women in urban Kenya, where in some areas the proportion of pregnant women infected plummeted from approximately 28 percent in 1999 to 9 percent in 2003.
In the Caribbean, declines are evident in Barbados, the Bahamas and Bermuda, Piot said.
"I absolutely believe we are on a roll," added Dr. Jim Kim, HIV chief at the World Health Organization. "Everyone is sort of jumping on the bandwagon. I think there's been a fundamental change, even in the past one year, in all the efforts in HIV."
About 1 million HIV patients in the developing world now are on treatment. About 300,000 deaths were avoided last year because of such treatments.
This year, the world has invested some $8 billion on tackling HIV in the developing world. UNAIDS estimates that $9 billion will be spent next year but say $15 billion will be needed.
