By using anti-retroviral treatments (ARVs) and mass screening, it is possible to stop the spread of AIDS in South Africa within five years, a top scientist has said.

"The cost of giving the drugs to almost six million HIV-positive patients in the country would be 2-3 billion dollars per year," said Dr Brian Williams, based at the South African Centre for Epidemiological Modelling and Analysis
(Sacema) in Stellenbosch.

He said that only about 30 percent get the life-saving drugs, but early detection and treatment would prevent transmission. This should be complementary to the search for an Aids vaccine.

An effective vaccine was still a long way away, said Williams, a leading figure in the field of HIV research.

The BBC quoted him as saying at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Diego," The tragedy is that the disease continues unabated. The only real success story is the development of these extremely effective drugs that keep people alive and reduce their viral load by up to 2,000 times. They become close to non-infectious."

He further added," While the rapid scale-up in the provision of ART in the last five years has exceeded expectations, it has not reduced HIV-transmission and Aids-related TB because it has been given too late in the course of infection."

Williams argued that by the time people started ART, they had infected "most of those that they would have infected anyway".

He said," We''ve been using drugs to save lives, but not stop the infection. It''s time to look beyond that." (With Input from Agencies)