International scientists on Thursday urged a new push for a cure to AIDS, saying the three-decade epidemic is outpacing medications to curb it.

The seven-step scientific strategy focuses efforts on key areas such as the reservoirs where human immunodeficiency virus (HIV) holes up in the body, and the small number of people worldwide who seem to have some natural resistance.

The plan was published in the British journal Nature and discussed at a press conference in Washington, which is hosting the International AIDS Conference on July 22-27, expected to draw 25,000 experts and advocates.

"Finding a cure for AIDS is a critical innovation gap," said Michel Sidibe, executive director of UNAIDS.

Leading experts have touted progress in the fight against AIDS in recent days, with eight million people in needy nations now receiving antiretroviral treatment and a drop in the death toll from AIDS in much of the world.

But the cost of treating people with HIV, about 34 million people worldwide, "is overwhelming many organizations and public health systems," said the article by the International AIDS Society in Nature Reviews Immunology.

The United Nations has called for $22-24 billion per year to help curb the AIDS epidemic by 2015, and antiretroviral treatment accounts for up to 70 percent of those funds in the most afflicted areas, according to background information in the article.

"It is estimated that for every HIV-infected person who starts antiretroviral therapy, two individuals are newly infected with HIV; this is clearly unsustainable," it added.

Instead, cure researchers need more funds and a renewed focus on a roadmap to curing AIDS, according to Francoise Barre-Sinoussi, the co-discoverer of HIV, and director of the regulation of retroviral infections unit at the Institut Pasteur in Paris.

"The science has been telling us for some time now that achieving a cure of HIV infection could be a realistic possibility. The time is right to take the opportunity to try to develop an HIV cure," she said.

She said additional cure funding should not take away from current programs to treat and prevent the disease.

"However, it is imperative that donors, governments and the AIDS community make viable economic investment in HIV cure research, and right now," Barre-Sinoussi said.

The strategy was devised by the International AIDS Society, a team of more than 40 scientists active in HIV research.

Some promising findings are pushing the renewed effort toward a cure, including the well-known case of an American man, Timothy Brown, who was given a stem cell transplant for leukemia from an HIV resistant donor and still appears disease-free several years later.

The donor came from a very small group of northern Europeans who lack a protein on the surface of white blood cells known as CCR5, which serves as the gateway for HIV to enter the cells.

While the transplant was too risky to be considered an option for the general public, the operation provides what scientists call "proof of concept" that a functional cure can be achieved.

Another intriguing group of people in France, known as the Visconti cohort, became infected with HIV but began treatment early and were able to stop it without the infection returning. Their immune systems are being intensely studied.

The report said a number of strategies being probed -- from gene therapy to immune treatments and vaccines -- would likely be more efficient in combination with each other and with the use of antiretroviral therapy to ready patients' immune systems for a cure.