Space Technology for TB Detection

The technology in question was a spectrometer developed for the European Space Agency's Rosetta comet-chaser and the Beagle 2 mission to Mars.

TB, caused by the Mycobacterium tuberculosis bacterium, is thought to kill two million people every year, mainly in developing countries. In countries such as these where resources are restricted, TB detection is usually carried out using a smear microscopy of sputum samples. This is not only a very labour-intensive process, but also has a low sensitivity.

Now a team of researchers has received funding to develop a portable mass spectrometer (an optical instrument used to measure the properties of light) for diagnosing TB.

"Smear microscopy is not a very accurate way of diagnosing TB and only detects a third of all positive cases," says project participant Dr Geraint Morgan of the Open University. "That means seven out of 10 patients will effectively need to get worse before they can be diagnosed and treated. Clearly we need a new solution to this problem."

"The thing with developing technology for space missions is that it forces you to push boundaries and think outside the box when you're looking for new solutions to challenging problems. Many of the technical challenges we have overcome in designing our space instruments are the same as we face with this issue," Dr Morgan explained.

Dr Morgan is leading the project with Professor Colin Pillinger, synonymous in the UK with the Beagle 2 mission to Mars, and Dr Liz Corbett from the London School of Hygiene and Tropical Medicine (LSHTM). Funding has come for the Wellcome Trust, a UK-based medical research charity.

Rosetta will be the first spacecraft to conduct scientific measurements on the surface of a comet. The Ptolemy instrument on board - a shoe-box-sized gas chromatograph mass spectrometer - will analyse small pieces of the comet's nucleus in order to identify what it is made from. This information should deepen our understanding of the make-up of the early solar system, as well as whether or not comets have ever been a source of water for life on Earth.

Dr Morgan and his team will now adapt this technology to create a spectrometer capable of detecting TB in sputum with greater sensitivity and speed than a smear microscopy. The process could also be automated, removing the need for skilled technicians and a specially equipped laboratory.

"Chemicals have their own unique 'signature'," says Dr Morgan. "The bacterium that causes TB has a special coating and it is the pattern of chemicals in this coating that the mass spectrometer will be searching for."

During the second year of the project, the device will be tested in Zimbabwe. According to the Global Fund, over 85,000 Zimbabweans had TB in 2003. The number of cases has rocketed over the last 20 years.

"We urgently need an accurate and cost-effective method of diagnosing TB," says Dr Corbett. "At the moment, because diagnosis is not accurate, people with TB may have to be seen up to 10 times before they can be started on TB treatment. They may be infectious throughout this period and, especially if they also have HIV, at considerable risk of dying before their diagnosis is made."

Professor Pillinger has praised the foresight involved in funding a project that brings together space research and health research. "It is very rewarding to see such vision paying off in clinical research," he said.

For more information on the Wellcome Trust, please visit:
http://www.wellcome.ac.uk