The 19th International AIDS conference kicked off Sunday amid a U.S. lag in reducing new HIV infections, the condition that has led to 35 million deaths worldwide.

More than 20,000 activists and researchers gathered for a week-long conference in Washington DC -- the first in the United States in two decades. Across the globe, the disease has struck young people in particular, killing many in the prime of their lives, creating multitudes of orphans and ravaging economies.

"Our return to the United States after a 22-year absence comes at a time of extraordinary hope, a time when we believe that the end of the AIDS epidemic is possible," said Elly Katabira, International Chair of AIDS 2012 and President of the International AIDS Society, in the opening session.

"There is no doubt, that our progress over the past 30 years has been impressive, but maintaining the status quo is simply not enough," said Diane Havlir, U.S. Co-Chair of AIDS 2012 and Professor of Medicine at the University of California, San Francisco.

"My message to policy makers around the entire world watching us here in D.C. is this -- invest in science, invest in the epidemic -- you will change lives."

In his address to the opening session through video, UN Secretary- General Ban Ki-moon said one year ago, the UN General Assembly set ambitious targets for 2015 -- to cut new infections by half, put 15 million people on treatment and ensure no child was born with HIV.

"We can achieve this target if we refocus, re-energize our mission, and invest more resources and also share experiences and take the next steps together," said Ban. "I'll support you. I'll continue to advocate for universal access to prevention, treatment, care and support. I'll continue to press the drug industry for access to affordable life-saving medicines. I'll continue to ask nations to respect and protect the rights of all those living with HIV."

World Bank Group President Jim Yong Kim also addressed the conference, the first time that a President of the Group has addressed the International AIDS Conference.

"I'm here to bring you both a pledge and a challenge," said Kim. "I pledge that the World Bank will work tirelessly with all of you here to drive the AIDS fight forward until we win. And I challenge you to join me in harnessing the moral power and practical lessons that the AIDS movement has produced to speed progress against that other global scourge, poverty."

After a quarter century of grappling with the disease, many countries have made significant strides toward slashing new cases -- including many in hard-hit sub-Saharan Africa.

However, the U.S. rate of new infections has remained unchanged at around 50,000 since the 1990s.

Indeed, a recent GlobalPost series on the issue found that Washington, the nation's capital, has a higher AIDS rate than five sub-Saharan African countries that received significant help to combat the disease under the President's Emergency Plan for AIDS Relief, or PEPFAR.

Thirty-four million people worldwide are HIV positive, including 1.2 million in the U.S.

The demographics of the disease have shifted in the U.S. since AIDS was first discovered in the mid-1980s, with African Americans now accounting for 44 percent of new infections.

"That's the group that we have failed to seek out aggressively enough, to test voluntarily, to convince them to get tested," said Anthony Fauci at the National Institute of Allergy and Infectious Disease in a video released recently by the Associated Press (AP).

Some activists have blasted U.S. President Barack Obama -- who will not appear at the conference, to the chagrin of AIDS activists -- for not contributing as much as his predecessor to fight the pandemic.

In 2003 former president George W. Bush said PEPFAR would allocate 15 billion U.S. dollars over five years to tackle AIDS, with a concentration on 14 African and Caribbean countries devastated by the disease and an emphasis on abstinence, marital fidelity and condoms.

Since then, Washington spent 32 billion U.S. dollars to fight the disease, and infections have dropped in more than 30 countries, most of them in sub-Saharan Africa.

Obama has promised to take action, unveiling two years ago a comprehensive strategy that aims to slash the number of new HIV infections nationwide by a quarter over a five-year period.

The president aims the plan at African Americans, Hispanics, drug users and gay and bisexual men, all considered the highest risk groups, who are statistically more likely to contract the disease than others.

Obama's plan also zeros in on the 12 U.S. cities where HIV and AIDS are most prevalent -- Los Angeles, Philadelphia, Washington DC, New York, Houston, Dallas, San Juan, Miami, Baltimore, Atlanta, San Francisco and Chicago.

The president vowed to give 4 billion U.S. dollars over three years to the Global Fund to Fight AIDS, Tuberculosis and Malaria. But some critics note that the funds are coming out of PEPFAR.

Last year Obama announced his intention to allocate public health funds to the tune of 50 million U.S. dollars to anti-AIDS medications in the country.

Still, despite the U.S. lag in cutting the rate of new infections, there is hope for what U.S. Secretary of State Hillary Clinton termed an "AIDS free generation." The AP's recent video said the pandemic has reached a turning point, as the focus is now on quickly getting care to newly infected patients in a bid to reduce the spread of the disease.

This week's conference agenda is jam packed from morning until evening, with dozens of experts panels ranging from the scientific to the medical to discussions on sex workers' rights. Secretary Clinton is slated to speak on Monday morning.

More than one panel focuses on sex workers advocates' charge that police in cities worldwide are using condoms as evidence against those engaged in commercial sex, which activists say endangers sex workers and their clients.

A Human Rights Watch report last week blasted police departments in New York City, San Francisco, Los Angeles and Washington DC for allegedly practicing such tactics. U.S. metropolitan police departments that Xinhua spoke to in San Fransisco, Los Angeles and Washington DC deny the claim.

The conference has come under fire from sex workers in India and dozens of other countries who alleged they have been denied visas to attend the event. They are holding their own conference in Kolkata, India.

Other panels will focus on HIV and AIDS among African Americans in the U.S. and blacks worldwide. Still others are expected to explore ways to improve U.S. AIDS policies.

The first International AIDS Conference occurred in Atlanta, Georgia, in 1985, and it was held in San Francisco in 1990. The conference was supposed to be held two years later in Boston, but the global research community refused to return to the United States because of its travel ban on HIV positive people. This ban was lifted by the Obama Administration in 2009.

VietNamNet/Xinhuanet