Tuberculosis (TB) is a contagious disease caused by the bacilli Mycobacterium tuberculosis, which usually attacks the lungs but can also attack the brain, spine, and other parts of the body. TB was once the leading cause of death in the United States but is much less deadly today due to the development of drugs and combination therapies to treat it; however, the development of drug-resistant strains of TB is cause for concern. Worldwide, TB remains a major cause of morbidity and mortality, particularly in Africa and South East Asia.

TB is spread primarily through the air, when a person with active TB puts the bacilli in the air through coughing or sneezing and other people breathe in the bacilli. When a person breathes in TB, the ...