The evidence backs up campaigners who for years have battled the pharmaceutical industry over access to antiretroviral drugs in Africa.
Two thirds of the nearly 39 million people living with AIDS or HIV live in countries south of the Sahara desert.
Aids programme success
US doctors reported on how the treatments were distributed to more than 16,000 patients in Zambia after the programme was expanded.
At the start of the programme, in April 2004, the patients were very badly infected.
Some "were literally arriving in wheelbarrows" at clinics to enroll in the program, said Jeff Stringer of the Centre for Infectious Disease Research in Zambia and the University of Alabama at Birmingham.
The drugs failed to save 1,142 patients whose immune systems had been virtually wrecked by the AIDS virus.
After 90 days, the mortality rate plummeted to levels equal to those in first world countries.
A year and a half later, "the vast majority" of patients had been saved enabling many to resume normal and productive lives, he said.
Pharmaceuticals proved wrong
Anti-retrovirals first emerged a decade ago.
But they remained restricted to the first world for many years even though HIV had a devastating impact on the south of the Sahara.
In the past, price prohibited many in the Third World from obtaining the drugs.
The drugs do not cure HIV, rather they merely control the virus at low levels.
They have to be taken every day, for the rest of the patient's life.
The pharmaceutical industry argued the drugs were highly complex and were designed for patients who access to medical services.
The regimen requires patients to take several tablets several times a day in conjunction with frequent lab tests.
The tests examine HIV concentrations in the blood and levels of CD4 immune cells.
Pharmaceutical giant, Big Pharma, warned if drugs were not taken consistently, the body could resist the drugs and reduce their effectiveness.
In 2003, ferocious campaigning by activists and competition from cheap generics manufacturers drove down the price of the drug.
Funds also flooded in to help the third world and a single pill combining three drugs in one was developed.
Dispelling fears that the drugs would have little effect in Africa, Mr Stringer said Zambia’s case proved that anti-retrovirals could be administered in an urban environment in a poor country.
Government leadership
Mr Stringer credited the programme’s success to the leadership and advocacy of the Zambian government, which scrapped fees for patients.
He also hailed AIDS funding from President George W. Bush; and a computer programme to help track patients' compliance.
Mr Stringer said another factor was the use of semi-skilled personnel to help implement the programme.
Nurses and health workers would monitor the patients and encourage them to take their medications, as a doctor would do.
This innovative approach was endorsed by Scott Hammer, advisor to former US president Bill Clinton's HIV/AIDS Initiative.
"The evidence to date shows that you don't need a fully entrenched medical system to deliver these drugs," Mr Hammer told AFP.
Instead of using lab tests to assess the initial viral load and immune-cell count, doctors can do a clinical assessment of the patient's health.
This determines whether he or she is sick enough to start taking antiretrovirals.
"With a standardised regimen and clinical diagnosis without the lab tests, you can deliver antiretrovirals and save lives," he told AFP.
As for compliance, the evidence is that Africans adhere far more closely to their antiretroviral treatment than HIV patients in rich countries.
They are often pressured by friends, relatives and other people in the community.
According to a study published last week in the Journal of the American Medical Association (JAMA), 77 percent of patients Africa adhered to the regimen, compared with 55 percent in North America.