Two-hour TB test may revolutionise treatment of killer disease

A new and novel fully-automated test that can detect TB, including drug-resistant forms, in less than 100 minutes could revolutionise treatment of the killer disease, the WHO said today, backing its roll-out across the globe.

The new nucleic acid amplification test (NAAT) could revolutionise TB care and control in countries like India by providing an accurate diagnosis for many patients in less than two hours, compared to current tests that can take up to three months to have results.

"This new test represents a major milestone for global TB diagnosis and care. It also represents new hope for the millions of people who are at the highest risk of TB and drug -resistant disease." said Dr Mario Raviglione, director of the World Health Organisation's stop TB department.

"We have the scientific evidence, we have defined the policy, and now we aim to support implementation for impact in countries," Raviglione said.

The current sputum smear microscopy test was developed over a century ago. Though there have been major improvements in TB care and control, tuberculosis killed an estimated 1.7 million people in 2009 and 9.4 million people developed active TB last year, the WHO said.

Controlling TB in India is a tremendous challenge. Every year, 1.8 million persons develop the disease, of which about 800,000 are infectious; and, until recently, 370,000 died of it annually —1,000 every day, according to latest official figures.

The current diagnostic test involves microscopic examination of a sputum sample and is far from ideal because it does not easily detect the growing number of strains that are resistant to antibiotics, or TB where the patient is co-infected with HIV.

Trials and demonstration studies have been carried out over 18 months in a number of different countries, involving more than 8,000 patients. The NAAT WHO says is simple and safe to use.

It incorporates modern DNA technology that can be used outside of conventional laboratories, although the need for a constant power supply may be a problem in rural areas.

The test been developed by the Foundation for Innovative New Diagnostics (FIND) with the private company Cepheid and the University of Medicine and Dentistry of New Jersey, The Guardian reported.

The major issue will now be cost. The market price for the equipment is USD 55,000 to 62,000, with an additional USD 55 to 82 for the cartridges it uses.