TB is a disease caused by a bacterium called Mycobacterium tuberculosis that can affect the lungs or other parts of the body. In most of the world and in Mbarara, Uganda, the method of diagnosis that is used is AFB smear microscopy. This method is widely available, inexpensive and rapid. However, this method's ability to truly detect people having TB is poor. That is, if someone has TB, the test results may say that they are negative, leading to delays in diagnosis, disease progression, and an ongoing transmission of the bacteria.