WASHINGTON (AP) —  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 U.S. capital later this month with a sense of optimism not seen in many years — hope that it finally may be possible to dramatically stem the spread of the AIDS virus.

“We want to make sure we don’t overpromise,” Dr. Anthony Fauci, the National Institutes of Health’s infectious disease chief, told The Associated Press. But, he said, “I think we are at a turning point.”

The big new focus is on trying to get more people with HIV treated early, when they’re first infected, instead of waiting until they’re weakened or sick, as the world largely has done until now. Staying healthier also makes them less likely to infect others.

That’s a tall order. But studies over the past two years have shown what Fauci calls “striking, sometimes breathtaking results,” in preventing people at high risk of HIV from getting it in some of the hardest-hit countries, using this treatment-as-prevention and some other protections.

Now, as the International AIDS Conference returns to the U.S. for the first time in 22 years, the 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 developed nations as well.

“We have the tools to make it happen,” said Dr. Elly Katabira, president of the International AIDS Society, which organizes the world’s largest HIV conference, set for July 22-27. He points to strides already in Botswana and Rwanda in increasing access to AIDS drugs.

But Fauci cautioned that moving those tools into everyday life is “a daunting challenge,” given the cost of medications and the difficulty in getting people to take them for years despite poverty and other competing health and social problems.

In the U.S., part of that challenge is complacency. Despite 50,000 new HIV infections here every year, an AP-GfK poll finds that very few people in the United States worry about getting the virus.

Also, HIV increasingly is an epidemic of the poor, minorities and urban areas such as the District of Columbia, where the rate of infection rivals those of some developing countries. The conference will spotlight this city’s aggressive steps to fight back: A massive effort to find the undiagnosed, with routine testing in some hospitals, testing vans that roam the streets, even free tests at a Department of Motor Vehicles office, and then rapidly getting those patients into care.

About 34 million people worldwide have HIV, including almost 1.2 million Americans. It’s a very different epidemic from the last time the International AIDS Conference came to the United States, in 1990. Life-saving drugs emerged a few years later, turning HIV from a death sentence into a manageable chronic disease for people and countries that can afford the medications.

Yet, for all the improvements in HIV treatment, the rate of new infections in the U.S. has held steady for about a decade. About one in five Americans with HIV don’t know they have it — more than 200,000 people who unwittingly can spread the virus.

Government figures show most new U.S. infections are among gay and bisexual men, followed by heterosexual black women. Of particular concern, African Americans account for about 14 percent of the population but 44 percent of new HIV infections.

Your ZIP code plays a role in your risk, too. Twelve cities account for more than 40 percent of the nation’s AIDS cases: New York, Los Angeles, Washington, Chicago, Atlanta, Miami, Philadelphia, Houston, San Francisco, Baltimore, Dallas and San Juan, Puerto Rico. Many are concentrated in specific parts of those cities.

Testing is a key step in improving prevention. The AP-GfK poll found 57 percent of adults say they’ve been tested at some point, a bit higher than federal estimates, but not enough. The government recommends at least one test for adults, and that populations at higher risk get tested at least once a year.

The government is targeting the hardest-hit communities as part of a plan to reduce HIV infections by 25 percent by 2015, said Assistant Secretary of Health Howard Koh. Work is under way to learn the best steps to get people treated early, including in cities such as Washington, where 2.7 percent of residents have HIV, roughly four times the national rate.