The report indicates that there is no single AIDS epidemic worldwide. Many regions and countries are experiencing diverse epidemics, some still in the early stages. “These latest trends firmly establish AIDS as a unique development challenge,” said Dr Peter Piot, UNAIDS Executive Director. “The time of quick fixes and emergency responses is over. We have to balance the emergency nature of the crisis with the need for sustainable solutions.”

According to the report, the number of people living with HIV globally has also reached its highest level with an estimated 39.4 million people, up from an estimated 36.6 million in 2002. The steepest increases in HIV infections occurred in East Asia, Eastern Europe,and Central Asia over the past two years.

In East Asia, the 50% increase in HIV infections from 2002-2004 is largely attributable to growing epidemics in China, Indonesia and Viet Nam. The 40% increase in Eastern Europe and Central Asia is mainly due to Ukraine’s expanding epidemic and the growing number of people living with HIV in the Russian Federation. With an estimated 860,000 people living with HIV at the end of 2003, Russia has the largest epidemic in Europe.

As the numbers of people becoming infected and living with HIV increases, so does the number of those needing antiretroviral treatment, as well as care for opportunistic infections. “We do not yet have a vaccine, but we do know that prevention and treatment work and we have the tools to deliver them. Government leaders, civil society and the private sector are all affected and we must all mobilise to save lives,” said Dr LEE Jong-wook, Director- General of the World Health Organization.

Women are more physically susceptible to HIV infection than men. Male-to-female HIV transmission during sex is about twice as likely to occur as female-to-male transmission.

For many women in developing countries, the “ABC” prevention approach (Abstinence, Being faithful and reducing number of sexual partners, and Condom use) is insufficient. "Strategies to address gender inequalities are urgently needed if we want a realistic chance at turning back the epidemic," said Dr Piot. "Concrete action is necessary to prevent violence against women, and ensure access to property and inheritance rights, basic education and employment opportunities for women and girls."

According to the report, millions of young people are becoming sexually active each day with no access to prevention services. In sub-Saharan Africa, three quarters of all 15-24 year olds living with HIV are female. Young women are three times more vulnerable to HIV infection than their male counterparts. In addition to being biologically more vulnerable to infection, many women and girls, particularly in Southern Africa, find themselves using sex as a commodity in exchange for goods, services, money, or basic necessities – often with older men. This “transactional sex” is mainly driven by poverty and the desire for a better life.

The UNAIDS/WHO report clearly indicates that there is no single, “African” AIDS epidemic. The epidemics throughout the continent are highly varied. Southern Africa continues to be the worst-hit region with HIV prevalence rates surpassing 25%. In Botswana, Lesotho, and Swaziland, prevalence rates still exceed 30% among pregnant women. Life expectancy has dropped below 40 years in nine countries in the region.

Despite modest declines in HIV prevalence rates in East Africa, notably in Uganda and parts of Ethiopia and Kenya, the epidemic is far from being reversed. In Addis Ababa, HIV prevalence fell to 11% by 2003, down from a peak of 24% in the mid-1990s. In Kenya, HIV prevalence fell from 13.6% in 1997 to 9.4% in 2002. The Caribbean continues to be the second worst-affected region in the world. HIV transmission occurs largely through heterosexual sex, although sex between men, which is highly stigmatized, is also fuelling the epidemic. AIDS has become the leading cause of death among adults aged 15-44 in the region.

In North America and Europe, an increasing number of people are becoming infected through unprotected heterosexual sex. In the United States, AIDS disproportionately affects African American and Hispanic women, with AIDS ranked among the top three causes of death for African American women aged 35-44 years. According to AIDS Epidemic 2004, there are strong indications that the main risk factor for many women acquiring HIV is the often undisclosed risk behaviour of their male partners.

In Western Europe, HIV infection through heterosexual sex more than doubled between 1997 and 2002. It is feared that large numbers of HIV-infected people are still unaware of their HIV status. In the United Kingdom, HIV has become the fastest-growing serious health condition.

Injecting drug use is on the rise in many regions and contributes to an increasingly large share of new HIV infections, especially in countries with emerging epidemics in Eastern Europe, Central Asia, and parts of Asia.

“In many countries, we are still seeing a mismatch between prevention spending priorities and the evolution of the epidemic,” said Dr Piot. “Men who have sex with men and injecting drug users continue to be neglected. More needs to be done to target them and increase access to prevention programmes for people at high risk of HIV infection.”

Global AIDS spending has tripled since 2001, from US$2.1 billion in 2001 to US$6.1 billion in 2004, and access to key prevention and care services has improved significantly. Yet the disease continues to spread. “Obviously more resources will be needed in the future, but right now the key challenge is making the money work – ensuring that available funds are spent effectively on where they are needed most,” said Dr Piot.

According to a recently published survey in 73 low- and middle-income countries (representing almost 90% of the global burden of HIV), the number of secondary-school students receiving AIDS education has nearly tripled, the annual number of voluntary counselling and testing clients has doubled, the number of women offered services to prevent mother-to-child HIV transmission has increased by 70%, and the number of people receiving antiretroviral therapy has increased by 56% between 2001 and 2003.

Despite the improvements, prevention and treatment coverage remains uneven in various regions. Less than one in five people has access to HIV prevention services in low- and middle-income countries. Between 5 and 6 million people are in need of HIV treatment. By June 2004, an estimated 440,000 people in the developing world had access to antiretroviral treatment, up from 200,000 two years before. Although the number of those receiving treatment has more than doubled, less than 10% of people who need treatment, predominantly in sub-Saharan Africa, are receiving it.

“AIDS treatment will only be viable if HIV prevention efforts are reinvigorated and vice versa,” said Dr LEE Jong-Wook. “Only by linking prevention and treatment can the global spread of AIDS be halted. We know that prevention works better when it is linked with the promise of treatment. We also know that unless we prevent new infections, millions more will be added to the “treatment list” every year, making treatment unsustainable.”

The annual AIDS Epidemic Update reports on the latest developments in the global AIDS epidemic. With maps and regional estimates, the 2004 edition provides the most recent estimates on the epidemic’s scope and human toll, explores new trends in the epidemic’s evolution, and features a special section on women and AIDS.

In January 2005, WHO will issue a formal progress report on what progress countries have made towards the "3 by 5" target to get three million on treatment by the end of 2005. The goal is universal access to treatment.