The days of TB complacency are over Tuberculosis (TB) is back with a vengeance and it has a new face: the combination of the HIV epidemic with new strains of the disease that are resistant to the existing drugs has seen new TB cases and TB-related deaths skyrocket in the last decade.

Mycobacterium TB, the bacterium that causes the disease, is ancient. But powerful antibiotics brought it under control in the developed world, scientists largely abandoned efforts to develop new drugs or diagnostics, donors stopped funding TB programmes and the global health community shifted its attention elsewhere.

The world, and sub-Saharan Africa in particular, is now paying the price. Very few countries in Africa have the technology to test for drug-resistant TB. Without sophisticated laboratory facilities, TB patients co-infected with HIV also present a diagnostic challenge.

In countries like Lesotho and Mozambique, lack of access to health services in remote, rural areas adds to the likelihood that large numbers of TB infections are going undetected and untreated, including cases of multidrug-resistant (MDR) and extremely drug-resistant (XDR) TB.

In Kenya, where overcrowded slums like those in the capital city of Nairobi create the perfect breeding ground for MDR-TB, there is some capacity to diagnose drug-resistant strains, but no treatment is available from public health services. Only a handful of patients access the drugs, which cost about 300 times more than those for standard TB treatment, from an international relief organisation, Medecins San Frontieres (MSF).

South Africa, with superior resources and laboratory capacity, is better positioned than most African countries to detect and manage the new, more dangerous forms of TB.

But experts say the country's TB control programmes have failed to adapt to the new threats of drug-resistance and HIV co-infection. Some have blamed South Africa's dismal TB cure rates on poor implementation of the WHO-recommended Directly Observed Short-Course Treatment (DOTS) for TB; others have called for a new, more patient-centred approach drawing on the strategies used for AIDS treatment.

With the outbreak of virtually untreatable XDR-TB in KwaZulu-Natal Province in 2006 the debate has widened to include the issue of infection control at health facilities, and the potential need for forced hospitalisation and treatment of infected individuals.

Talk of quarantine could add to the stigma that already prevents many people from seeking TB treatment: in the Johannesburg township of Soweto, the strong association between TB and HIV means that people suffering TB symptoms often prefer not to seek treatment rather than face the possibility of being HIV-infected.

TB has always affected the most marginalised groups of society, which may explain why the disease has fallen off the public agenda. A recent report by an international development nongovernmental organisation (NGO), Panos, says even when journalists do cover TB, they usually fail to explore the links between TB, poverty and other socio-economic factors, or interview people affected by the disease.

World TB Day on Saturday 24 March is an opportunity for activists, health practitioners and journalists to push for a greater sense of urgency in TB responses, particularly in the context of southern Africa's already crushing HIV burden.