Dramatically expanding the use of anti-retroviral drugs could almost completely eradicate HIV/AIDS worldwide in just two generations, says a team of Canadian researchers.

Treating patients with a combination of drugs known as "highly active anti-retroviral therapy," or HAART, reduces the level of HIV virus in patients' blood until it is no longer detectable, which reduces their ability to infect others.

Unfortunately, though, more than two-thirds of the population who qualify for anti-retroviral drugs are not receiving them. These individuals are fueling the expansion of the epidemic.

Quarantining the Virus

The spread of HIV/AIDS could be vastly reduced -- from the current seven cases per 1,000 to fewer than 0.1 case per 1,000 -- in just 45 years, according to the study, which was led by Dr. Julio Montaner at the British Columbia Center for Excellence in HIV/AIDS. The researchers' findings are published in The Lancet.

Those percentages work out to a reduction in the current number of HIV-infected people from roughly 40 million to about 1 million.

This is possible, the researchers contend, because the drugs could do more than stop the progression of HIV to full-blown AIDS -- they could prevent its transmission altogether, in essence, establishing a "chemical quarantine" around the virus.

"The prospect of treating 40 million HIV-infected individuals worldwide seems daunting today," the researchers acknowledge, "but in view of the limited effect of current efforts on global prevention of new infections, this approach merits consideration if it can offer a means to control the relentless growth of the pandemic," they argue.

Currently, HIV-infected patients do not receive anti-retroviral drugs until their immune functions have declined to a specific level. There are two main reasons for postponing use of the medications: cost and side-effects. What that means, though, is that while patients slowly deteriorate to the point where treatment can begin, they continue to be infectious.

The researchers propose that the cost savings gained from the prevention of new infections would more than offset the upfront expense of using HAART therapy much earlier.

Where's the Fire?

Critics say the plan is unworkable for several reasons. First among them is the expectation that many patients would not be willing to endure the unpleasant side- effects of the HAART therapy if they were not convinced that taking the drugs was necessary for their survival.

The list of side-effects is long and varied -- from the common problems of fatigue, nausea and diarrhea to the less-common but more severe occurrences of diabetes, heart disease and neurological effects, to name just a few.

There is also the thorny challenge of discovering who actually is HIV-positive. Health experts estimate that about a quarter of the infected population do not know their status.

The fact that so many people with full-blown AIDS are dying for lack of treatment leads some to question the practicality of a proposal that involves a massive expansion of the number of people who should get the drugs.

One doctor compared the idea to ignoring an inferno while pouring water on a place that wasn't burning.

Too Costly, or Cost-Effective?

It is undeniable, though, that where the anti-retroviral drugs have been used in the past 10 years since they became available, rates of new infections have dramatically subsided. In North America, for example there are 3.1 new infections per year for every 100 people already living with HIV/AIDS. In contrast, there are 14.7 new infections per 100 people with HIV/AIDS in Eastern Europe, and 14.3 per 100 in Africa.

Where data has been gathered on the use of HAART, dramatic results have been observed. In British Columbia and Taiwan, for example, free access to the program led to a reduction in new HIV cases of about 50 percent.

Expansion of the program would not only reduce the number of cases of HIV, but also make HAART therapy much more cost-effective in the long term, the researchers emphasize.

The $15 billion cost of treating all the world's HIV-infected people today would be more than offset by the savings gained by preventing new cases, they conclude.