Jacquelyn Martin, Associated Press
In this photo taken June 27, 2012, Katherine Tapp, 26 of New York City uses an oral test for HIV, inside the HIV Testing Room at the Penn Branch of the District of Columbia Department of Motor Vehicles, in southeast Washington. An AIDS-free generation: It seems an audacious goal, considering how the HIV epidemic still is raging around the world. Yet more than 20,000 international HIV researchers and activists will gather in the nation's capital later this month with a sense of optimism not seen in many years _ hope that it finally may be possible to stem the spread of the AIDS virus.

Researchers say they see a "turning point" in the international battle to squash transmission of HIV, which leads to AIDS.

Key, they say, is early treatment, since healthier people are less likely to infect others. But it won't be cheap or easy and there's still much to be learned about the best approach to tackle spread of the deadly virus, given the ongoing HIV epidemic worldwide.

"We want to make sure we don't overpromise," Dr. Anthony Fauci, National Institutes of Health infectious disease chief, told the Associated Press. "I think we are at a turning point."

Fauci is one of more than 20,000 HIV experts from all over the world who will gather in Washington, D.C., July 22-27, for the International AIDS Conference. It has been two decades since the conference was last held in the United States.

Associated Press says the big question is "whether the world will come up with the money and the know-how to put the best combinations of protections into practice for AIDS-ravaged poor countries and hot spots in the developed nations, as well."

Despite availability of AIDS medications, it's a "daunting challenge," according to Fauci, because those drugs are expensive and it's not easy to get people to take medications for years on end "despite poverty and other competing health and social problems."

Joe DeCapua explains in a Voice of America piece the concept of "treatment as prevention": "Recent studies have shown that antiretroviral drugs not only extend the lives of people infected with HIV, but can also prevent infection in the first place. ... It now means countries have the potential to greatly slow the spread of HIV by using the drugs as a prophylaxis. However, often those in need of HIV treatment and prevention are unable to receive them because of their social status."

Two recent studies have shown the strategy works. One focused on couples where one person is HIV positive and the other HIV negative. "The drugs were 96 percent effective in preventing the HIV negative person from being infected," DeCapua wrote. Another study showed that treatment prior to exposure to the virus could prevent transmission.

News articles hailed that finding in 2011, after the research from the University of North Carolina-Chapel Hill was published in the journal Science. It was selected as No. 1 in a top 10 reckoning of AIDS-related breakthroughs by the journal.

Science, which notes that most of the world's 34 million HIV infections worldwide are transmitted by heterosexual contact, featured results of two trials that showed "that giving relatively safe and inexpensive antiretroviral (ARV) pills each day to uninfected people dramatically reduced the risk of heterosexual transmission of HIV. ... so progress in this area could be a game-changer. Before PrEP can be widely used, however, the field must wrestle with myriad practical, ethical and financial issues."

World Health Organization officials have long said the initial costs of such preventive use of drugs would be very expensive, but savings from not having to treat people after they were infected would be far greater.

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