EXTREME STRAIN OF TB APPEARS IN S AFRICA

by Moyiga Nduru

(IPS) JOHANNESBURG -- For the region in the world worst-affected by AIDS it is, to say the least, an unwelcome development: an outbreak of tuberculosis (TB) in South Africa's southeastern KwaZulu-Natal province, caused by a strain of the disease that resists almost all forms of treatment.

To date, 52 of the 53 patients known to have been infected died within about 25 days of the disease first being suspected, said a statement by delegates at a meeting currently underway in the South African financial center of Johannesburg to discuss how TB resistance can best be dealt with. The two-day gathering, which ends Friday, has brought together TB experts from the World Health Organization (WHO) and elsewhere.

"This extremely high mortality is in part explained by the fact that 44 patients tested were all HIV infected; 15 of these were receiving ARVs (anti-retroviral drugs). Nevertheless all died with XDR-TB," the statement noted.

XDR-TB -- Extensive or Extreme Drug Resistant TB -- is a more severe form of Multidrug Resistant TB (MDR-TB). While strains of MDR-TB are resistant to at least two of the main drugs used to treat TB in the first instance, isoniazid and rifampicin (known as "first-line drugs"), XDR-TB is also resistant to various second-line drugs -- the final weapons against the disease.

Ordinary forms of TB were already known to be of particular concern to people infected with HIV, whose immune systems are too weak to fight the disease. The emergence of XDR-TB puts AIDS patients at even greater risk.

"A global survey reported earlier this year that XDR-TB is present in every region of the world. However, a recent outbreak in the KwaZulu-Natal province in South Africa highlighted the risk of XDR-TB for HIV-infected people," observed the statement.

These words were echoed Thursday by Dr Karin Weyer, TB Research Director at the South African Medical Research Council, an organization largely funded by government.

"Southern Africa is the epicenter of HIV and TB. We need to act fast. If the new strain of TB gets out of control, it will pose a major threat to the region and beyond," she told a media briefing given alongside the Johannesburg meeting.

"HIV has the potential to fast track XDR-TB into an uncontrollable epidemic. Infection control precautions are needed now, and must be scaled up without delay in settings where HIV patients are brought together."

Added Ken Castro, director of the Division of Tuberculosis Elimination at the U.S. government's Centers for Disease Control and Prevention, "TB has no borders. This is why we want to control it as a matter of urgency."

The Joint United Nations Program on HIV/AIDS estimates that Southern Africa is home to about one in three of all people living with HIV/AIDS (globally, 38.6 million people were HIV-positive last year, according to the agency). For its part, the Southern African Development Community puts the number of people with HIV/AIDS in the region at more than 14 million.

TB becomes resistant to drugs through a variety of factors, which include patients failing to complete courses of TB medication, incorrect prescription of the drugs, and provision of poor quality drugs.

"New anti-TB drugs are desperately required to treat XDR-TB patients," noted the statement issued at the Johannesburg TB conference.

But, "Research into these new agents has only recently been revitalized and despite promising drugs in the pipeline, these will not be available for at least five years. Further investment in new drug research and development will be necessary to ensure an adequate number of effective drugs."

Simply diagnosing XDR-TB in Southern Africa can be problematic.

"In South Africa we have six laboratories. In the region, most countries have only one laboratory at the main hospital in the capital," said Meyer.

However, South Africa is not without its problems in this respect, noted Professor Willem Sturn of the Nelson Mandela School of Medicine at the University of KwaZulu-Natal.

"We are better off in South Africa than many other African countries," he told journalists. "But our rural areas are dispersed, making it difficult to control the disease."

For the immediate future, delegates at the Johannesburg meeting advise health workers to follow a seven-point action plan that stipulates -- amongst others -- rapid surveys of XDR-TB, improving the ability of health workers to deal with XDR-TB outbreaks, putting in place precautions against infection, and promoting universal access to ARVs.

Globally, TB claims 1.7 million lives a year, according to the WHO.