Several big firms, such as Eskom, De Beers, the world's biggest diamond producer, and miner Anglo American have in the past few years stepped up efforts to test their workers for HIV, and treat infected staff -- in a bid to save their bottom lines...Some 40 South African firms have joined the GBC [Global Business Coalition on HIV/AIDS], including Barloworld, Telkom, SAB Miller, Sappi, FirstRand, Old Mutual, Liberty Group [Liberty Life] and many run similar AIDS programmes for their workers...But the biggest challenge was being faced by small firms.