Tuberculosis (TB) is a very contagious bacterial infection caused by Mycobacterium tuberculosis. It usually affects the lungs but can affect any part of the body.  A person should get tested for TB if s/he has been around an infected person or suspects that s/he may have been exposed to the infection. The Mantoux tuberculin skin test, also known as the PPD test, is a screening tool to test a patient’s exposure to tuberculosis.  This test only reflects whether the patient has been infected with TB bacteria, and cannot distinguish whether s/he has latent TB infection or TB disease.  It is important to have a trained healthcare provider carefully and properly administer the test for the best chance of an accurate reading.