"The epidemic is extremely severe, it's worse than any of us admit to, there are a lot of undiagnosed cases that don't get reported," Brian Brink, medical senior vice-president at Anglo American...Over two decades later, with up to one in three infected and South Africa the centre of a global pandemic, the firm says its own prevention efforts failed...The world's fourth biggest gold producer, Gold Fields, has estimated the total cost from HIV at around $5 per ounce of gold produced in South Africa, and even with gold trading at around $650 per ounce the cost is significant...In China, the U.N. estimated 650,000 people were infected in 2005, up by 23 percent in two years. If that spread continues, some 1.9 million people will be infected in China by 2015...Remote mine sites attract sex workers. In the mining province Yunnan in China, sex workers from Myanmar and Vietnam are a high-risk group likely to spread the disease as illegal migrants fear the threat of deportation if they contact public health services. [Also mentions BHP Billiton, and Barrick Gold.]