Laboratory work is being undertaken to refine a relatively simple TB biomarker that could provide a more sensitive and specific test for the screening and diagnosis of active TB infection.
Burnet Institute received a tuberculosis (TB) biomarkers grant through the Bill & Melinda Gates Foundation’s Grand Challenges in Global Health program.
There is an urgent need for an effective diagnostic test that can detect and differentiate active and latent TB infection, in both adults and children, and in populations drawn from countries with both high and low prevalence of TB.
The current diagnostic tests for TB infection commonly give false positive results when testing individuals from countries in which TB is highly prevalent, because their prior exposure to TB (even when not resulting in latent or active infection, or in patients previously cured of a TB infection) makes them reactive in the Mantoux skin test and the blood-based Interferon Gamma release assays (IGRAs).
Alternative tests based on sputum specimens are more specific (i.e., giving less false positives results), but are only effective in symptomatic patients with pulmonary TB, missing significant numbers of cases such as pleural or meningeal TB, and subclinical infections. In addition, sputum collection is not possible for babies and very difficult for children.