Webb County provides tuberculosis skin tests (TST) and directly observed therapy (DOT) to Webb County residents.Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis, a germ that is spread from person to person through the air. TB usually affects the lungs, but it can also affect other parts of the body, such as the brain, the kidneys or the spine. A person with TB disease can die if they do not get treatment. TB disease can be cured with medical care and the right medicine.