Around a third of the world’s population is infected with the TB bacteria and approximately 9 million new cases of active TB are diagnosed around the world each year, according to World Health Organisation estimates. The majority of those infected live in the developing world.
The new ELISpot blood test is able to identify patients with a significant risk of developing the active form of TB, according to the study, carried out by researchers from Imperial College London working with international colleagues.
Patients with active TB experience the symptoms of the disease, which include fever, persistent cough, and loss of appetite, whereas patients with the dormant, ‘latent’ form of TB do not. Treatment can prevent many patients with latent TB from progressing to active TB.
The researchers believe that the ELISpot blood test can enable preventative treatment to be targeted in a more focused way than the tuberculin skin test. Unlike the blood test, the skin test commonly gives falsely positive results if a patient has previously been vaccinated against TB.
The blood test will allow doctors to identify and treat those who need preventative treatment whilst reducing the numbers treated unnecessarily, thus avoiding the attendant risks of drug side-effects, according to the researchers. This is especially important in the developing world where there are limited resources for both testing and treatment.
Today’s research looked at 908 children in Istanbul, Turkey, who had recently been exposed to TB in their household. Of these, 594 tested positive for latent TB using the ELISpot blood test, the skin test, or both.
Of 550 children who tested positive for TB with the skin test, 12 went on to develop active TB. Fewer children tested positive for TB with the blood test (381), but the test still picked up 11 of the 12 children who went on to develop active TB.
Children with a positive ELISpot blood test result had approximately a four-fold higher risk of developing TB disease than children with a negative result. A higher proportion of children with a positive ELISpot blood test result developed TB disease compared to children with a positive TB skin test.
As a precautionary measure, 76% of the children in the study had been given prophylactic treatment to prevent them from developing active TB. This meant that the researchers could not determine the proportion of children who would have gone on to develop active disease had they remained untreated. Nonetheless, the study identified a significant risk for children with a positive ELISpot blood test result of developing active TB, despite the majority having received treatment, and this risk is therefore an underestimate of the risk in untreated children.
Professor Ajit Lalvani, the lead author of the study and a Wellcome Trust Senior Clinical Research Fellow at the Centre for Respiratory Infection at Imperial College London, said: “A lot of people in places like the UK think of TB as being an old disease that we no longer need to worry about, but even in this country the numbers of cases have been rising for almost 20 years. Outside the developed world, TB has reached pandemic proportions and still causes an immense amount of suffering and death.
“Our study shows that new tools like the blood test can help tackle the global pandemic. We now know that the blood test really helps to target treatment to those who most need it in order to prevent them from developing active TB. Building on this work, we are now validating a next generation of tests that have been developed by our TB Task Force at Imperial,” added Professor Lalvani.
The ELISpot test, which was created by Professor Lalvani and colleagues, works by detecting a protein signal, known as interferon-gamma, released by white blood cells of the immune system in response to TB infection. The test has been recommended for use alongside the skin test in around 20 countries worldwide, including the EU and North America.
Professor Lalvani leads a new, specially created TB Task Force at Imperial College London and Imperial College Healthcare NHS Trust, who together have formed an Academic Health Science Centre (AHSC). The AHSC aims to bring the benefits of research to patients much more quickly than ever before. The TB Task Force carries out research to develop and deploy effective new weapons in the battle against TB.
This study was funded by the Wellcome Trust; the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases; and the Sir Halley Stewart Trust.
The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung
A sudden drop in outdoor temperature increases the risk of respiratory infections
11.01.2017 | University of Gothenburg
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences