A full-scale rollout of HIV treatment and available prevention methods could avert 6.75 million new infections and 4.7 million AIDS-related deaths in China and South Africa alone, according to a study presented Wednesday, July 21, at the XVIII International AIDS Conference (IAC), taking place July 18 to 23 in Vienna.

Experts at IAC reported on the first day of the conference that annual deaths from HIV are declining globally—from 2.2 million in 2004 to 2 million in 2008—largely due to the scale-up of antiretroviral (ARV) therapy in sub-Saharan Africa and other developing nations. Nevertheless, the study's authors stress that HIV is far from being under control. An estimated 2.7 million new infections occur each year, and at the current pace, for every two people put on ARV treatment, nearly five become infected.

New HIV prevention methods are beginning to bear fruit. The resounding success of the CAPRISA 004 tenofovir microbicide trial means that within a few years there could be an important new female-controlled prevention method available. In the meantime, Kelsey Case—a PhD student at the Imperial College London's Institute for Global Health—and her colleagues estimated what could happen during the next 20 years if ARV drugs were rolled out to everyone who currently needs them and all current prevention methods were fully employed and promoted in two countries: South Africa and China.

Case's team used up-to-date estimates of HIV transmission and deaths in each country and then factored in the benefits of a variety of treatment and prevention methods as had been documented in other studies. Case and her colleagues looked at not only the estimated influence of ARV treatment rollout, but also all currently proven HIV prevention tools, including: voluntary counseling and testing, mass media, condom promotion and distribution, education and outreach programs, and male circumcision.

The authors found that a “bold scale-up” of these interventions between now and 2015 would result in 1.25 million new infections and 700,000 AIDS deaths in China by the year 2031, and 5.5 million infections and 4 million AIDS deaths in South Africa. With all of the approaches employed, Case's team estimates that nearly 75 percent of all new infections (an estimated 2 million per year) could be prevented. To accomplish this by 2031, however, more than 300,000 HIV-positive individuals in China and 2.2 million individuals in South Africa would have to be receiving ARV therapy.

While this is no small task, some experts feel that a large financial push now would not only save lives, but also ultimately save tens of billions of dollars later.

“Our simulations show that most new infections and deaths by 2031 could be avoided if appropriate actions are taken in the next few years,” the authors conclude. “However, the results show that irrespective of our collective efforts now, AIDS will continue to affect millions of lives for the next several decades and that any failure to scale-up interventions immediately could quickly lead to overwhelming [ARV treatment] costs, increased deaths and further spread of new infections.”