The most significant of these is the HPTN052 randomized control trial, which found that earlier antiretroviral treatment can reduce the risk of heterosexual HIV transmission by as much as 96 percent; other studies have proven the efficacy of ARVs for prevention in HIV-negative people.

"We need to ensure that the advances we are making in research - such as the now proven concept of antiretroviral treatment as a means of HIV prevention - are translated into action for people in developing countries," said IAS local co-chair Stefano Vella, research director at Italy's Istituto Superiore di Sanita, at the official opening of the conference.

But translating the research into action will require money, and if recent trends are any indication, that will be difficult, and there is much scepticism about the ability to significantly increase the numbers on treatment with such limited funds.

Donor pressure

"We need to keep up the pressure on donors... Donors are used to seeing costs rising year after year, but now we can show them a light at the end of the tunnel... We can show them that investing today will lead to lower costs tomorrow," Brenda Waning, coordinator of market dynamics with the health financing mechanism, UNITAID, said. "We also need to learn how to do more with limited resources."

Treatment as prevention will mean putting significantly more people on treatment earlier; at present, 15 million people are estimated to need ARVs - only 6.6 million have access to them.

"Treatment as prevention is possible, it is feasible, but we must not fool ourselves into thinking it's going to be easy," said Paul de Lay, deputy executive director of UNAIDS. "We put an additional 1.4 million new people on treatment in 2010 - if we maintain that momentum we will not achieve the goal of 15 million on treatment by 2015.

"We need to get to US$22 to $24 billion a year from the $15 billion a year we are currently spending; we need African governments to abide by the Abuja Declaration commitment to spend 15 percent of national budgets on health and we need donors to meet their commitments," he added.

"If we can convince donors that we can stop the epidemic within a finite amount of time, the money will be found," said Brian Williams, an epidemiologist with the UN World Health Organization (WHO).

Scaling-up HIV testing

Key to putting more people on treatment earlier will be finding those who need it; according to De Lay, most countries with hyper-endemic epidemics are testing just 4 percent of their populations.

"We can't rely on VCT alone; there has to be a massive push for provider-initiated counselling and testing," he added. However, "we have seen some classic human rights violations when it comes to HIV testing: lack of confidentiality, stigma and discriminatory practices and mandatory testing... we must ensure testing is done with respect for human rights."

According to Reuben Granich, medical officer for TB and HIV at WHO, testing will have to expand in innovative ways to achieve the levels necessary for treatment to be effective as prevention.

"We have to go beyond the health facility to community-based testing; for example, household testing, multi-disease prevention campaigns - malaria, safe water, HIV testing and so on," he said. "None of this will work without community demand and engagement."

UNAIDS executive director Michel Sidibe said his organization was working with Jeffrey Sachs and the Earth Institute to mobilize more than one million community health workers in Africa by 2015.

Monitoring, drugs

Millions more people on treatment will create a need for increased monitoring - including CD4 testing, which measures immune strength, and the more accurate but more expensive viral load testing - to keep tabs on treatment failure and prevent drug resistance.

In sub-Saharan Africa, most tests are conducted at centralized laboratories, often taking weeks and losing patients needing treatment in the process.

"New diagnostic technology will help overcome barriers to treatment and testing," said UNITAID's Waning. "We are hoping to see disposable CD4 tests and expect the first viral load point-of-care tests to be available by 2012 at an affordable price."

Pharmaceutical companies will have a role to play, both in lowering the cost of drugs and in ensuring new ARVs. "Pharmaceutical companies need a new business model - one in which they can make profits and continue to conduct research and development while keeping the price of drugs affordable," said De Lay.

"We must oppose trade agreements that seek to limit TRIPS [Trade Related Aspects of Intellectual Property Rights] flexibilities. I want to salute the government of India for refusing to accept provisions on data exclusivity. And I want to recognize the leadership of the BRICS [http://www.unaids.org/en/resources/presscentre/featurestories/201 1/july/20110711bchinabrics ] [Brazil, Russia, India, China and South Africa] ministers of health in ensuring that trade does not undermine access to medications, especially generics," said Sidibe.

He pointed out the importance of using all the prevention tools available, and the need to keep using tried-and-tested methods like condoms. HIV prevention has also recently received a boost in the area of pre-exposure prophylaxis, with a number of studies - including a large randomized control trial based on daily oral ARVs and a separate study involving a microbicide gel - also showing efficacy in preventing HIV.

"Even if treatment as prevention is rolled out in the most optimum way, it is unlikely to capture everyone infected... PrEP does have a role, especially microbicide gels in hyper-endemic countries," said De Lay.

"We have to remember that history will judge us not by our scientific breakthroughs, but how we apply them," Sidibe.

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