For the first time in the 20-year history of the AIDS epidemic, just as many women as men are infected with HIV.
The virus is spreading most rapidly in Eastern Europe, where 10 years ago HIV was confined to small geographical areas.
"The number of new infections in Eastern Europe, Central Asia, Baltic States has increased by one quarter, so the epidemic is still in a major expansive phase," said Dr. Peter Piot, executive director of UNAIDS.
However, Piot said, virtually every country is experiencing a major outbreak.
"The high income countries are seeing an increase in unsafe sexual behavior of syphilis and other traditional sexually-transmitted diseases," he told the conference.
It has also marched swiftly across Central Asia and into China, where it was almost nonexistent a few years ago.
"In about every Asian country, HIV is expanding," Piot said.
But there are signs of hope. The AIDS Epidemic Update, an annual report by the World Health Organization and UNAIDS, gives the first signal that prevention programs are working in the few areas where they have been set up.
"There are a number of countries where we have strong empirical evidence that rates of infection are declining, and in each case they are declining among young people," said Piot. "We have examples in Addis Ababa in Ethiopia; in South Africa, where HIV infections among pregnant teenage girls fell by a quarter between 1998 and 2001.
In Uganda, every year for the last 10 years there have been fewer new HIV infections than the year before, he said.
"This positive trend is the first signal that there is an impact of the prevention and education programs," Piot said.
However, those successes are isolated cases and HIV continues its sweep.
"It's once more a sad story — 42 million people living with HIV today, 5 million new infections in 2002 and 3.1 million died from AIDS this year," Piot said.
There is not only an increase in the sheer number of people being infected, but also an increase in the number of countries now facing epidemics, said Dr. Bernhard Schwartlander, director of the HIV/AIDS division at the World Health Organization.
All the countries in Eastern Europe now have an HIV problem within less than a decade of seeing HIV.
"We have seen that no society is immune," Schwartlander said. "Even though HIV was quite well established in many Asian countries very early on, we had seen a very stable low rate in a number of countries. It was just at the point in time where people were starting to think maybe these societies are immune. We have been shown different."
"In Indonesia, after many years of silence, of very low rates," an epidemic is growing, Schwartlander said. "Of course HIV was there, but it didn't really lead to major epidemics. It was just over the past couple of years that massive spread of HIV has begun, initially in injecting drug users.
"In China, again HIV was virtually nonexistent only a couple of years ago, but we now have 1 million people living with HIV/AIDS in China," he said, adding that experts estimate that infections there could climb to 10 million by the end of the decade. Injecting-drug users are a major factor in the Chinese epidemic.
Sub-Saharan Africa is still by far the worst affected region. The situation there also reflects the feminization of AIDS. About twice as many young women as men are infected there, the report found.
In 2001, between 6 percent and 11 percent of young women aged between 15 and 24 had HIV, compared with between 3 percent and 6 percent of young men in the same age group.
It is particularly difficult for women there to follow prevention recommendations because of their subordinate position in society in many regions.
A recent study found that in Zimbabwe, rape is common and that negotiating for safe sex to prevent HIV infection is almost impossible for many adolescent girls because involvement with older men in return for such benefits as clothes and school fees is widespread.
The phenomenon of intergenerational sex is driving much of the epidemic in Southern Africa, where between one-quarter and one-third of older men are HIV positive.
The shift toward women will ultimately exacerbate the spread of HIV, Piot said, because from women it can be spread not only through sex, but through breast-feeding. HIV drugs prevent the spread from mothers to babies.
The report also found that the new dynamics of the HIV epidemic aggravate the famine in sub-Saharan Africa, where it is the women who work the fields.
"AIDS is fueling the food crisis in sub-Saharan Africa. This is the first large-scale sign of what the impact of AIDS can and will be for society as a whole," Piot said.
Alan Whiteside, director of the Health Economics and HIV/AIDS Research Division at the University of Natal in Durban, South Africa, said it is clear that AIDS is not just a health crisis, but also a development crisis.
The virus is causing an economic crisis in Southern Africa, he said, and worsens political crises in places such as Zimbabwe.
"In a situation where life expectancy has plummeted it's very hard to keep them engaged in a future when they don't believe they have one," Whiteside said.