In 2010, an expansion in access to treatment helps cut the number of AIDS-related deaths, says the United Nations.
"We are on the verge of a significant breakthrough in the AIDS response," said Michel Sidibe, executive director of UNAIDS. "New HIV infections continue to fall and more people than ever are starting treatment," he noted.
Speaking to journalists in Berlin for the presentation of the report, Sidibe hailed what he called a "game-changing year."
"For the first time we are able to demonstrate that if you put people early on treatment you can reduce the number of new infections," he said.
About half of those eligible for treatment are now receiving it, with the most dramatic improvement in access seen in sub-Saharan Africa, which recorded a 20-percent jump in people undergoing treatment between 2009 and 2010.
As a result of better access to healthcare, the number of AIDS-related deaths was also falling, said UNAIDS, the UN agency spearheading the international campaign against the disease.
In 2010, 1.8 million deaths were linked to AIDS, down from a peak of 2.2 million last seen in 2006.
"An estimated 700,000 AIDS-related deaths were estimated to have been averted in 2010 alone," added the UN agency.
Not only is treatment helping to prevent new AIDS-related deaths but it is also contributing to a drop in new HIV infections.
Patients undergoing care were less likely to infect others, as prevention programmes coupled with treatments were proving effective.
Modelling data suggests that "the number of new HIV infections is 30 to 50 percent lower now than it would have been in the absence of universal access to treatment for eligible people living with HIV."
In Namibia for instance, where treatment access reached an all-time high of 90 percent and condom use rose to 75 percent among men, the combined impact contributed to a 60 percent drop in new infections by 2010, noted UNAIDS.
"I want to say this report is clearly showing that even in those difficult period (three years of financial crisis) we are still having a result: we have more and more countries which are reducing the number of new infections," said Sidibe.
The UN agency added that the full preventive impact of treatment was likely to be seen in the next five years, as more countries reach high levels of treatment coverage.
"The massive increases in the numbers of people receiving treatment in South Africa between 2009 and 2010, for example, are likely to be reflected in substantially fewer new infections in the near future," it said.
UNAIDS assessed that even if the AIDS epidemic is not over, "the end may be in sight if countries invest smartly."
"In the next five years, smart investments can propel the AIDS response towards achieving the vision of zero new HIV infections, zero discrimination and zero AIDS-related deaths," it said.
However, the turning point is coming at a time when industrialised nations' public budgets are being squeezed and translating to less international funding for the AIDS response.
Medical charity Medecins Sans Frontieres urged governments to keep up their funding.
"Never, in more than a decade of treating people living with HIV/AIDS, have we been at such a promising moment to really turn this epidemic around," said Tido von Schoen-Angerer, who heads MSF's access campaign.
"Governments in some of the hardest hit countries want to act on the science, seize this moment and reverse the AIDS epidemic. But this means nothing if there's no money to make it happen."