Researchers at a conference in Los Angeles have said that as many as 85% of HIV-positive South Africans are also infected with an extensively drug-resistant form of tuberculosis (TB), Extensive Drug Resistant TB (XDR-TB).
The researchers suggest that XDR-TB is continuing to increase because of globally widespread flaws in the treatment of TB.
According to Karin Weyer of South Africa's Medical Research Council, cases of XDR-TB have been found in 40 hospitals in South Africa, as well as in every province in the country, adding up to a total of around 600 cases.
XDR-TB is resistant to the two most potent first-line treatments isoniazid (Nydrazid) and rifampin (Rifadin) and also to some of the available second-line drugs, and many patients have died.
Although XDR-TB does not seem to spread easily, it does pose a threat to people and health care workers who are HIV-positive and since September 2006, about 183 people, most of whom were HIV-positive, have died from XDR-TB in the country.
XDR-TB is expected to exacerbate the HIV/AIDS epidemic in South Africa, where about five million out of a population of 45 million people are HIV-positive and as many as 1,000 people die of AIDS-related complications daily.
According to the World Health Organization (WHO), the number of countries with XDR-TB cases has increased from 17 in March 2006 to 28 currently.
According to the Center for Disease Control (CDC) the most-affected countries include South Africa, South Korea and parts of Eastern Europe.
Weyer says XDR-TB creates a huge challenge in terms of infection control, especially in settings where high numbers of HIV-positive individuals are converging, such as hospitals.
Paul Nunn, the coordinator of WHO's TB drug-resistance unit, says the 85% mortality rate is "completely egregious" and it is important to increase awareness about XDR-TB worldwide without causing undue alarm.