Using the rapid test health workers can make an accurate diagnosis of TB within 100 minutes compared to current methods that require patients to wait up to 48 hours for straightforward TB results and weeks for drug-resistant tests. Patients often die while waiting for these results, are lost to follow-up or go on to infect others while they wait to be placed on treatment.
Current treatment standards in most countries require of patients to give sputum at least twice after which sputum smear microscopy is used to make the diagnosis ‘ a development that is more than a century old. If the result is positive the patient is put on treatment. Sputum smear microscopy is not always accurate especially in HIV-positive patients.
Dr Mario Raviglione, director of WHO’s Stop TB Department said the new test was a major milestone in 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. We have the scientific evidence, we have defined the policy, and now we aim to support implementation for impact in countries,” he said.
The WHO’s stamp of approval for the rapid test comes after 18 months of painstaking testing to verify its effectiveness in diagnosing pulmonary TB and more difficult forms including drug resistant TB and TB aggravated by HIV.
Implementing the fully automated NAAT (nucleic acid amplification test) could result in a three-fold increase in the diagnosis of patients with drug-resistant TB and doubling in the number of HIV associated TB cases in areas with high TB and HIV.
Added to the stamp of approval is a call made by the WHO for the easy to use rapid test to be rolled out as far and wide as possible under clearly defined conditions. It would be part of the national plans for TB and MDR TB care control.
One of the key concerns has been affordability. The Foundation for Innovative and New Diagnostics, a co- developer, announced that it had negotiated a 75 percent price reduction with the manufacture, Cepheid for the benefit of countries most affected.
Favourable pricing will be granted to 116 low and middle income countries with a high burden of TB as well as an additional reduction in price if there is high demand for the test.
Dr Giorgio Roscigno, FIND’s chief executive officer said, there was a strong commitment to overcome all the barriers including those posed by money.
“For the first time in TB control, we are enabling access to state-of-the-art technology simultaneously in low, middle and high income countries. The technology also allows testing of other diseases, which should further increase efficiency.’