Breathalyser detects tuberculosis

A simple breath test could detect tuberculosis

Coughing into a breathalyser could be the new way to detect the most common form of tuberculosis.

The portable device, developed by Rapid Biosensor Systems, would be quicker and easier to use than the current screening method, called the Heaf test.

The Heaf test involves an injection of tuberculin into the skin. The patient has to wait one week to see if a reaction develops, which would indicate exposure to infection.

Tuberculin is a fluid containing the products formed by the growth of the bacterium which causes TB.

Rapid Biosensor say they can deliver 90% accurate results in under 10 minutes.

The breathalyser is also disposable, cheap and has the potential to screen for other diseases, although it cannot be used as a diagnostic tool.

It can also be used by someone with no formal medical training.

How it works

The breathalyser works through an optic sensor which sits inside the tube. This sensor has a coating designed to attract bacteria.

When the patient coughs into the tube, sputum is brought up - a secretion produced in the lungs where tuberculosis can reside.

If TB is present in the lungs, it will stick to this optical sensor, giving a positive reading.

Dennis Camilleri, CEO of Rapid Biosensor Systems said they are in the process of trialling the device in the UK and in India, and hope to apply for a company licence by May this year.

"We may find our process is accurate enough to be used as a diagnostic tool," he said.

"We have done trials with ecoli bacteria, which have shown the sensor can detect bacteria easily. Making the jump to TB is not much more complicated."

A spokesperson for TB Alert, a tuberculosis awareness charity, said: "We would like faster, simpler methods of diagnosis."

The device is quick to use and disposable

"At the moment a patient has to be seen twice and that already leads to complications.

"Furthermore, if the test does show infection, then the patient has to be properly diagnosed, which involves an X-ray or sputum analysis."

However Dr Kate King, at Cambridgeshire and Peterborough Health Protection Unit said that as the breathalyser could only test for one type of TB, it was unlikely it could entirely replace the current screening method.

She said around one third of tuberculosis cases involved infection in other organs, such as kidneys, lymph nodes, brain tissue, bones and joints.

"This new device has potential value to people who have tuberculosis in their lungs," she said.

"This is the only form of the disease that is infectious, and people with it will be sicker than those with tuberculosis infection elsewhere."

Global emergency

The rate of tuberculosis has steadily risen in the UK over the past 17 years, increasing by 34% since 1987.

In 2002 almost 7,000 people contracted the disease.

Globally, around 8 million people contract TB each year, and two million will die as a result.

In 1993, the World Health Organisation declared tuberculosis a 'global emergency'.

Dr King said: "It is a serious health problem worldwide - and a lot of people in the UK have family links to countries where TB is common.

"The classic symptoms are lung infection, chronic cough that lasts for weeks, fever, night sweats and weight loss. it can also infect the lymph nodes and kidneys."

"It is pretty much a disease of the disadvantaged - alcoholics, drug users, and those living rough, because of poor diet, inability to maintain their own health and bad hygiene.

Tuberculosis can lie dormant in a person for years and then strike when the immune system is weak.

"It is often seen in people over 60 who were first infected as a child," Dr King said.

Most cases can be treated with a six-month course of antibiotics.

Children in the UK are routinely given the Heaf test and a BCG vaccine between the ages of 10 and 14. According to the NHS, the vaccine provides around 70% protection and lasts for around 15 years.