Beneath South Africa's gold mines there is a seemingly impenetrable tuberculosis (TB) epidemic spreading through the majority of the workforce. Yet this public health disaster is largely unheard of beyond South Africa's mining regions. Instead, local union strikes and the fluctuating price of gold, as well as deepening cost pressures on industry, have tended to dominate discussion about this part of the mining world.

But the truth is, in South Africa, and possibly the rest of Africa's mines, too, pulmonary TB is a serious problem affecting miners' health as well as that of their families and finances. It is also squeezing companies' profits due to increased medical costs and reduced productivity.

You have to look at the statistics supplied by non-profit biotech company Aeras, which works to advance TB research and development, to comprehend the problem: of the 2.3 million new cases of TB reported in Africa last year, 760,000 - almost a third - were connected to mining in sub-Saharan Africa. Nine out of ten gold miners in South Africa are latently infected with TB and one mine worker with active TB can spread the disease to between ten and 15 other people.

A study published in the New England Journal of Medicine this year says HIV infection and exposure to silica dust in ultra-deep mines, along with close working and living conditions predispose South African gold miners to TB.

The economic price of TB

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According to Aeras, the TB epidemic is costing the mining industry $570m in productivity costs, while miners lose $320m per year in wages. TB treatment costs the South African government and mining industry more than $360m per year. The industry employs over one million people and accounts for 18% of South Africa's GDP.

"The mining industry, in particular gold and platinum, has some of the highest rates of TB in the world, if not the highest," says Aeras vice president of external affairs Kari Stoever. "We have some data that says the economic toll of TB in South Africa is estimated to be about $1.3bn per year, which accounts for cost to the industry in lost wages, direct cost to the industry in treatment and money from lost wages for the government itself which co-operates with the miners ensuring they have access to treatment."

A spokesperson from one of the leading gold mining companies in South Africa, AngloGold Ashanti, said the company is aware of the problem: "We are certainly cognisant of the gravity of the TB problem in South Africa as a whole, and therefore also in the gold mining industry. Over the past decade we have intensified our efforts to address this issue."

TB is also thought to be a problem in other African mining nations, such as the Democratic Republic of Congo, where TB is endemic, and Ghana, but Stoever says it's impossible to know for sure because the data isn't being collected.

Troublesome treatment solutions

TB is an infectious and often fatal disease caused by various strains of mycobacteria. It attacks the lungs and is spread through the air when people who have an active TB infection cough or sneeze.

""Nine out of ten gold miners in South Africa are latently infected with TB and one mine worker with active TB can spread the disease to between ten and 15 other people.""

Worryingly, TB isn't cheap or straightforward to treat and treatment can be complicated even further if a patient has HIV. Stoever says treatment for straightforward TB is six months of antibiotics followed by ensuring the patient is not infectious before returning to work in the mine. For drug-resistant TB, treatment is a combination of highly toxic drugs for up to two years. In some mine treatment centres this can cause a sanatorium-type lockdown until the workers' sputum clears.

Currently there is no vaccine for TB in adults. There is a common misconception that the Bacillus Calmette-Guérin vaccine (BCG) given to school children around the world can protect against adult respiratory TB , but it is much less effective in protecting adults against this type of TB than it is children.

Mining companies, particularly the bigger ones, have largely been addressing the TB epidemic attacking its miners head-on. Stoever, speaking after visiting hospitals run by both AngloGold Ashanti and Anglo American Platinum, said both companies are doing an "outstanding" job of finding TB cases and ensuring miners are getting the appropriate treatments but adds that she is sure "some [companies] have better practises than others".

AngloGold Ashanti says it has had some success in reducing the incidence rate of TB. The company said in 2006 the TB incidence rate [percentage of employees who develop TB during the year] in its South African operations was 4.3 % and through sustained and multifaceted interventions, it has reduced the incidence rate to 1.8 % in 2012, a 58% reduction from the 2006 figure. It added that all patients remain in employment throughout the course of their treatment.

Despite these positive results the company recognises that "more challenges remain"

However, a recent study published in The New England Journal of Medicine showed disheartening results. The Thibela TB study, the largest study of its kind on the South African mining TB epidemic, studied 78,744 miners in 15 gold mines from 2006 to 2011. Miners from eight mines were screened for TB and given necessary treatment or a nine-month course of isoniazid preventive therapy, while the other seven mines continued their TB control programs as usual.

The results, published in January 2014, showed that the intervention treatment did not reduce the incidence of TB, although it did show a reduced incidence of TB during treatment. However, as soon as treatment was stopped there was rapid loss of protection. Therefore twelve months after the study, researchers did not find any difference in the number of cases of TB in those who had preventative therapy and those who didn't.

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The next chapter: finding a long-term solution

In the wake of the disappointing trial results, Aeras is currently in discussion with the Chamber of Mines in South Africa and many mining executives to find an alternative long-term solution.

Stoever is clear in which direction she'd like the talks to turn. "If there is a solution," she says, "it is going to be partnership between civil society, the union, a partnership with the corporations and a partnership with the government, where each individual group understands what this is costing them today."

It is vital for all parties to understand the cost implication of this epidemic to them, she says, adding: "South Africa went from being number one in production of gold to sixth in the world but they are number one for cost. If you can mine in Canada, America, South East Asia for a third of the cost that you can in South Africa that is not a tough decision to make and I think that is one of the risks [for investors] in South Africa."

If the situation worsens, which is possible due to concerns over drug resistance, companies may start to divest of their assets in South Africa.

To find a long-term solution that will benefit miners, mining companies and the government, who all rely heavily on a thriving mining industry, Stoever says Aeras wants to create a 'virtuous cycle' related to the markets.

""We have some data that says the economic toll of TB in South Africa is estimated to be about $1.3bn per year.""

She explains: "If we could somehow look at gold as a commodity, gold as a natural resource, gold as a big driver of economic development in the South Africa region... and figure out a way to create this virtuous cycle where we then put money into the health system to fight infectious diseases like TB and HIV both with our current tools, which have their limitations, but also in research and development, where we really have a our best bet in potentially eliminating TB and HIV with vaccines in the future. This isn't an act of charity; this is real bottom line business for families and communities."

AngloGold Ashanti says it also recognises a collaborative approach is needed and that it is willing "to partner with like-minded stakeholders to find durable solutions".

"The fight against TB is a collective responsibility of all the role players in society - people in their individual capacity, organised business, organised labour and other organs of civil society," the company's spokesperson says.

Right now a vaccine seems to be the only viable long-term solution but Stoever admits that, although research and development has improved from no TB vaccine candidates in 2000 to 13 today, six of which Aeras is working on, a usable vaccine is still ten years away. The key to Aeras's solution is convincing mining companies and the government that a vaccine is worth investing in, which, on a basic business level, if a mine has a 20-plus life span, it surely is. For African governments it is imperative they invest now before the TB epidemic grows worse, destroying the lives of African families as well as the continent's true mining potential.

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