"We are on scientifically solid ground when we say we can end the HIV/AIDS pandemic," said Anthony Fauci, Director of the U.S. National Institute of Allergy and Infectious Diseases.

The optimism is due in part to recent discoveries that people living with HIV treated with antiretroviral therapy can prevent the virus from being transmitted to others—treatment-as-prevention, as experts define. The drugs prevent the virus from replicating, reducing the level of active viruses in blood and other body fluids that are the usual vehicles for infection. And further research shows that good treatment can cut by 96 percent their chances of spreading the virus to sexual partners.

"We are at a defining moment," Havlir said. "We know that starting the end of AIDS will not be easy. We need to keep sprinting in this marathon."

AIDS-free generation

AIDS, the acquired immunodeficiency syndrome, was first recognized in the United States in 1981. Back in the 1980s, it was largely a disease of economically stable, white, gay men living in big cities on the west and east coasts. But today, HIV, the human immunodeficiency virus which causes AIDS, disproportionately infects African-American men who have sex with men, and the epicenter of the epidemic is in the poverty-stricken Deep South.

"In the richest nation on the planet, barely a quarter of people with HIV are in fully effective treatment. More than 70 percent are either not in treatment at all or suboptimal treatment," Phill Wilson, President and CEO of the Los Angeles-based Black AIDS Institute, said at a plenary on July 23. "That's bad for them and it's bad for everyone else because when they are not on treatment, they are much, much more likely to spread the virus." Wilson called on AIDS organizations to retool themselves and adapt to the new landscape.

"We want to get to the end of AIDS," said Fauci, but how long it takes depends on how quickly the world can adopt those tools—including getting more of the millions of untreated people onto life-saving drugs that come with the bonus of keeping them from infecting others.

Testing-and-treatment is one of a series of factors that create a vast gap between HIV infection and control of the infection. The other challenge, which was also one of deep anxieties running through the entire meeting, is where the money will come from to keep the AIDS effort going forward, since "funding has stagnated since the 2008 financial crisis, and for many programs it has plummeted," said Laurie Garrett, a senior fellow for global health of the New York City-headquartered Council on Foreign Relations.

"We now have a funding gap of $7 billion per year for HIV. This gap is killing people," said Sidibe.

Domestic funding for HIV has exceeded international investments, according to the UNAIDS report. Low- and middle- income countries invested $8.6 billion for the response in 2011, an increase of 11 percent over 2010. International funding, however, remained flat at 2008 levels ($8.2 billion).

On July 23, U.S. Secretary of State Hillary Clinton announced a number of commitments to support AIDS prevention worldwide, including $80 million to help poor countries and an additional $15 million on research to identify the best HIV prevention tools to reach those key populations in different countries. "The United States is committed and will remain committed to achieving an AIDS-free generation," she said.

As an echo to her, former U.S. President Bill Clinton, whose foundation funds HIV work, called for helping turn the tide against the HIV/AIDS epidemic at the closing plenary session. "We have you to thank for the progress that has been made and you to make us believe we can achieve an AIDS-free generation," he said. "We just have to keep pushing the rocks up the hill."

The Clinton Foundation started the Health Access Initiative in 2002 to increase affordable access to health care globally. The foundation's efforts in the area have lowered the costs of treatment and increased access to life-saving medical technologies.

Active participation

Among the various sessions in AIDS 2012, a case study presentation about Methadone Maintenance Treatment (MMT) for AIDS attracted clinical professionals' attention. Conducted by Han Lifeng with the Division of Global HIV/AIDS of the U.S. Centers for Disease Control and Prevention in China, the presentation provided a qualitative study of MMT among persons who inject drugs in three provinces in China.