According to the Mail & Guardian Online
researchers estimate that the mining industry in Africa might be implicated in as many as 760,000 new cases of tuberculosis each year, due to factors such as silica dust in mines, crowded working and living conditions, and the spread of HIV.
"Men travelling from afar to work in mines, such as from Botswana to South Africa, are at the greatest risk of getting tuberculosis," the study found.
"But their wives, children, and friends are also at high risk when miners travel back and forth to work, often many times a year."
The report, published in the American Journal of Public Health, said that the lack of continuity of care as miners travelled across borders was the biggest problem and suggested that mines in Africa should routinely screen miners in order to detect tuberculosis at an early stage.
The study also highlighted the need to improve poor working conditions and reduce the miners' exposure to silica dust.
The 2009 Global TB Control Report released by the World Health Organisation (WHO) has found that although the incidence tuberculosis (TB) remained relatively stable year-on-year, one in four TB deaths is HIV related - twice as many as recognised in the previous year.
This is largely due to the improved quality of data shown by the increase in HIV testing amongst people being treated for TB in Africa.
Fourteen percent of the 9.27mn estimated world-wide cases of TB in 2007 – about 1.37mn cases – are believed to have involved the co-infection of TB and HIV. Seventy-nine percent of these HIV-positive cases were in Africa according to the WHO report.
“Three quarters of all TB patients in South Africa are HIV positive,” said Professor Salim Karim, director of the Centre for AIDS Programme of Research in South Africa (CAPRISA) based in Durban, South Africa.
Karim, who is leading research into recurrent TB infections to ascertain whether the are as result of a relapse or re-infection with a different strain of TB, said that there is a high risk of re-infection for the 700,000 people on Aids treatment programmes in South Africa.
He explained that in much of South Africa the clinic facilities where people are treated are “overcrowded and poorly ventilated” and that it places some of the most highly infectious cases of TB in close proximity to people who are immune compromised and carry a high risk of contracting TB.