New Blood Test Proven Six Times More Effective for TB Detection


 
 

| Wednesday, February 27, 2008


In a landmark study electronically published in the American Journal of Respiratory and Critical Care Medicine, a blood test for detecting TB infection, QuantiFERON(R)-TB Gold (QFT(TM)), has been shown to be six times more accurate than the conventional tuberculin skin test (TST) at predicting which tuberculosis (TB)-exposed individuals will go on to develop TB disease. This study has important implications for the worldwide effort to eradicate TB, as accurately indentifying TB-infected individuals allows health authorities to treat them before they develop disease, and the greater accuracy of the new test makes this more efficient as well as cheaper and safer (see also Tuberculosis).

Globally, up to two billion people are infected with TB. In most cases the TB bacteria is contained by the body's immune system (latent TB infection) without any symptoms of the infection. But 9 million people, most originating from this large pool of individuals with latent TB infection, are reported every year by The World Health Organization as developing active and infectious TB disease.

In the developed world, TB eradication strategies have focused on identifying and treating people with latent TB infection. Until recently the tuberculin skin test (TST; Mantoux test) has been the only test available to detect infected people. However, the TST often produces false-positive results, meaning many uninfected people are offered unneeded preventative treatment for TB. This treatment is for 6 to 9 months and may produce damaging side effects. For improved TB control, a test that accurately detects those truly infected, enabling treatment for only those at risk of developing TB disease, has major implications. The QFT test has now been shown to have this desired characteristic.

In the German city of Hamburg, Dr. Roland Diel and colleagues used both TST and QFT on 601 people who may have been infected by contact with people with TB disease. 40% had a positive TST, but only 11% (66) of the exposed persons were found infected by QFT and offered TB treatment -- 41 declined. Over the next two years 6 people developed TB disease, all were QFT positive and had declined treatment. In the past, all 243 TST positive people would need to have had anti-TB treatment to prevent only 5 of these cases, as one was TST negative. In scientific terms, QFT had a predictive value for developing TB disease of 15%, more than 6 times greater than the 2.3% for the TST.

What does this mean? Using QFT, doctors can now treat only a fraction of the people they would have with the TST, with the knowledge that they are preventing TB disease to at least the same extent, and likely better.


Connect: Have a thought or feedback about this? Add your comment now
Related Topics: Industry News, PPE and Infection Control, Research

What's Your Take? Comment Now ...

Buyer's Guide Featured Companies

Featured Careers & Jobs in EMS

Get JEMS in Your Inbox

 

Fire EMS Blogs


Blogger Browser

Today's Featured Posts

 

EMS Airway Clinic

Mechanical CPR is Producing Resuscitation Results Beyond Expectations

Discover why clinical studies are finding mechanical CPR just as effective as optimally-performed CPR.
More >

Multimedia Thumb

New Technology Helps Missouri Ambulances

Strategic GPS tracking helps in Springfield.
Watch It >


Multimedia Thumb

Profile: Hospital Wing Air Ambulance

Take a look inside this Memphis service.
Watch It >


Multimedia Thumb

New Monitors for Wyoming EMS

Grant helps Torrington EMS get new equipment.
Watch It >


Multimedia Thumb

London Medics Increasingly Attacked

One medic describes her violent confrontation.
Watch It >


Multimedia Thumb

Violence, Arson in Ferguson

Crowds in Ferguson and elsewhere react to decision.
More >


Multimedia Thumb

California Bus Rollover

One killed and dozens injured.
More >


Multimedia Thumb

Buffalo Residents Dig Out and Prepare for Flooding

Flooding expected as heavy snow melts.
More >


Multimedia Thumb

Braun Ambulances' EZ Door Forward

Helps to create a safer ambulance module.
Watch It >


Multimedia Thumb

VividTrac offered by Vivid Medical - EMS Today 2013

VividTrac, affordable high performance video intubation device.
Watch It >


Multimedia Thumb

The AmbuBus®, Bus Stretcher Conversion Kit - EMS Today 2013

AmbuBus®, Bus Stretcher all-hazards preparedness & response tool
Watch It >


More Product Videos >