The bacterium Mycobacterium tuberculosis causes tuberculosis (TB), a contagious, airborne infection that destroys body tissue. Pulmonary TB occurs when M. tuberculosis primarily attacks the lungs. However, it can spread from there to other organs. First-line treatment options include isoniazid, rifampin, ethambutol, and pyrazinamide. While some people with active TB require a short hospital stay, many can receive treatment at home. Most people start feeling better and are no longer able to pass on the infection after a few weeks of treatment.