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IGRA stands for Interferon-Gamma Release Assay. It is a diagnostic test used in the detection of tuberculosis (TB) infection, particularly in individuals who have been exposed to TB bacteria but do not show symptoms of active disease. Unlike the tuberculin skin test (TST), which requires the injection of purified protein derivative (PPD) into the skin and subsequent measurement of the immune response, IGRA is a blood test that directly measures the release of interferon-gamma by T cells in response to TB-specific antigens. IGRA tests, such as the QuantiFERON-TB Gold test and the T-SPOT.TB test, offer several advantages over TST, including greater specificity, reduced likelihood of false-positive results due to prior Bacillus Calmette-Guérin (BCG) vaccination or exposure to non-tuberculous mycobacteria, and the ability to distinguish between TB infection and BCG vaccination. IGRA tests are recommended for individuals at higher risk of TB infection, such as healthcare workers, immigrants from TB-endemic regions, and those with HIV infection or other immunocompromising conditions. The results of IGRA tests can help healthcare providers determine the need for further evaluation, treatment, and preventive measures to control the spread of TB within communities. Despite their advantages, IGRA tests are not without limitations, including variability in test performance, cost, and the need for specialized laboratory facilities and trained personnel for sample processing and analysis. Ongoing research efforts aim to improve the accuracy, accessibility, and cost-effectiveness of IGRA testing for TB diagnosis and surveillance.