Green light for rapid TB test

The World Health Organisation (WHO) has approved a new rapid test for Tuberculosis (TB) and drug-resistant TB that will lead to results being available within 100 minutes.

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 or go on to infect others while they wait to be placed on treatment.

Current treatment standards in most countries require 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 however 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.

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 nucleic acid amplification test (NAAT) 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 prevalence of TB and HIV.

Added to the stamp of approval is a call made by 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 (FIND), a co- developer, announced that it had negotiated a 75% 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."
 
Source: Health-e news 08.12.2010 Lungi Langa