Evaluation of Exposure to Tuberculosis Among Employees at a Medical Center
Tuberculosis (TB), a disease caused by the bacteria Mycobacterium tuberculosis (M. tuberculosis), is spread from person to person through the air. TB usually infects the lungs, but it can also infect other body parts such as the brain, kidneys, or spine. People who are infected by the bacteria but who do not exhibit symptoms have latent TB infection. It is estimated that one-third of the world's population has latent TB infection, and approximately 5%–10% of those infected will develop TB disease within their lifetimes.(–)
In July 2011, the National Institute for Occupational Safety and Health (NIOSH) received a health hazard evaluation request from management representatives at a medical center in Arizona concerning exposure of employees to M. tuberculosis. They asked for our assistance in evaluating the infection control and occupational health practices related to TB.
At the time of our visit, the medical center included an inpatient hospital with 73 beds and adjacent outpatient facility, and the center had approximately 1000 employees. One nurse, the infection control practitioner, was responsible for all infection control and occupational health activities at the medical center. The medical center's TB policy required annual tuberculin skin testing (TST) of all employees with face-to-face patient contact, which included the majority of employees.