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TB Blood Test (QFT)
A tuberculosis blood test, also known as a Quantiferon (QFT) is an alternative to the tuberculin skin test (PPD). The blood test detects Mycobacterium tuberculosis through the measurement of a cell-mediated immune response. The blood test is able to evaluate latent or active TB infections, is not affected by the BCG vaccines, and requires one visit as opposed to 2 or 4.
TB Skin Tests (PPD)