South Africa's mining giant AngloGold has begun providing anti-retroviral drugs to HIV-positive employees - the first such business in the country to do so.

The treatment is being supplied initially to those considered most at risk of developing full-blown Aids.

AngloGold estimates that up to 30% of its 40,000 workforce is infected with the virus.

Its parent company Anglo American said in August it would make anti-Aids treatment available to all its South African workers.

Activists have campaigned for the greater availability of retrovirals

South African diamond mining company De Beers made a similar announcement shortly afterwards.

Although the price of such drugs is falling, treatment is still not available to the general public in South Africa's state-run hospitals and clinics.

South Africa has one of the highest infection rates in the world, with an estimated one in nine of its population of 42 million declared HIV-positive.

Counselling

Three employees received their first prescriptions for the so-called triple cocktail drugs - the potentially life-saving but expensive and complicated therapy - at the West Wits and Vaal River gold mines.

"We expect a steady inflow of more patients over the next few months", AngloGold HIV/Aids manager Petra Kruger said.

Initially, about 200 volunteers are to take part in the scheme and will be monitored.

Estimated infection rate among gold miners

1986: 0.5% 2001: 30%

They receive counselling about the treatment and its implications before they have to decide whether to go ahead.

It is proposed that the scheme will be expanded to all eligible patients who want it from April next year.

The company believes that not all who are HIV positive would need the drugs immediately, and not all staff would want to be tested.

"For society's sake, we hope others follow us," AngloGold Chief Executive Officer Bobby Godsell said.

Cost-effective

The cost per day to the company for the triple cocktail therapy is reported to be between two and three dollars per patient.

An earlier study by the company suggested that treatment would add $4-6 - or up to 2% - to the cost of producing an ounce of gold.

But it warned that the cost of the disease would rise to $9 per ounce if no action were taken.