By Eric Onstad CARLETONVILLE, South Africa, July 11 (Reuters) - After years of limited success cajolling and pleading with miners to take voluntary tests to check their HIV status, mining firm Gold Fields adopted modern marketing tactics. "We said 'let's up the game, let's dangle a carrot so people can come and know their status'," said Stella Ntimbane, group HIV/AIDS coordinator for Gold Fields. Now each of the company's South African miners who takes an HIV/AIDS test gets a lottery ticket, offering chances at monthly prizes of cell phones, televisions and cash, plus a final sweepstake. One lucky worker will drive away in a new pick-up truck. It is just one example of how firms are stepping up the battle against a disease affecting up to one in three miners. They are also sending mobile treatment units to the bush near mines where sex workers operate and blanketing the region with millions of condoms. Gold Fields' game, which also pits the company's mines against each other to win the big final prize, has gone a long way to overcome fear and denial linked to HIV/AIDS. "We're getting queues at the testing stations, it's like 1994," Ntimbane said, referring to the year when new black voters flocked to polls to elect Nelson Mandela president. Since October, more than 5,000 miners have taken tests, accounting for nearly a quarter of the total 22,000 taken by Gold Fields workers during more than a decade. Gold Fields employs around 43,000 permanent workers in South Africa. If tests reveal full-blown AIDS, workers are offered free anti-retroviral treatment to curb progress of the disease. BROTHELS IN THE BUSH Gold companies in South Africa, the world's biggest producer of the precious metal, have also banded together to cut HIV infection when migrant workers visit sex workers. "You are not going to stop miners from going there... So we give education to them, how to change their behavour. If they want to co
