New test to revolutionise TB diagnosis
December 9, 2010 in medical news
The World Health Organisation (WHO) has endorsed what it says is a revolutionary new way of diagnosing tuberculosis.
The test can be done on the spot in 100 minutes compared to the weeks and months it has traditionally taken in a highly equipped and secure laboratory.
It was co-developed by scientists in the US, Geneva and a drug manufacturer and is expected to help save many of the 5,000 people who die every day worldwide from the treatable lung illness.
WHO head of TB diagnostics Dr Karin Weyer says all countries are being urged to roll out the technology, including Australia.
“The new test is revolutionary in several ways,” she said.
“Number one, it diagnoses TB and drug-resistant TB simultaneously in an assay that takes only 100 minutes in a machine that looks a little bit like a coffee machine where one puts the sputum in,” she said.
“You switch the machine on and everything is done inside the machine. A hundred minutes later the computer screen provides a result and also tells you if that TB is drug-resistant or not.”
Dr Weyer says in some countries up to 30 per cent of tuberculosis cases can be drug-resistant.
She says the new test will revolutionise how tuberculosis is diagnosed around the world.
“We expect to see at least a three-fold increase in the number of patients with multi-drug-resistant TB detected with this test,” she said.
“And in HIV settings we’ve seen a doubling of cases being detected with this test.
“As a result of that, we also hope to see a significant decline in deaths from tuberculosis, especially in HIV-positive patients where often by the time the diagnosis gets back to the patient, the patient has already died.”
She says low and middle-income countries will receive a 75 per cent reduction in the cost of the test.
“As demand and volumes rise there will be more significant reductions over the next year to two years to a point where the test will not be more than $10,” she said.
“That is 50 per cent of what we are paying today for doing some of the older tests.”
While there could be a rapid increase in the number of people diagnosed with tuberculosis with the new technology, Dr Weyer says there will also need to be extra treatment available.
But she says the treatment, especially for the drug-resistant strand of the disease, is “hugely expensive”.
“So countries do have to rely at this point on donor funding to help them scale up the treatment also,” she said.
She says in countries like Australia, where there are only about 1,000 new cases every year, the new test is still recommended.
“It’s completely safe. It can be done in a doctor’s consulting room and patients would benefit from having a diagnosis immediately,” she said.