Burden of Occupationally Acquired Pulmonary Tuberculosis among Healthcare Workers in the USA: A Risk Analysis

Abstract

Pulmonary tuberculosis (TB) infection remains an occupational health burden among healthcare workers (HCWs), but current surveillance data do not allow for attribution of pulmonaryTB disease to occupational or community exposures.The objectives of this study were to estimate the annual number of occupationally acquired pulmonaryTB infections among HCW in acute care settings (ambulatory care, emergency departments (EDs), and hospitals) in the USA, and to estimate the impact of increased compliance with respiratory protection. We used a risk analysis approach, in which occupational exposures were modeled using a compartmental model of bacilli transport and fate, and infection risk was estimated using two dose–response (DR) functions. With the conservative Wells–Riley DR function, we estimated 6420 occupationally acquired pulmonaryTB infections annually in the USA, on average; with the more likely animal-based DR function, we estimated 3288 occupationally acquired pulmonaryTB infections annually in the USA, on average. Increased (95%) compliance with respiratory protection would eliminate about one-third of pulmonaryTB infections. Using results from the animal-based DR function, we estimated 82 cases of pulmonaryTB disease will develop among US workers annually, on average, given 50% of infected HCW receive effective chemoprohylaxis and 5% of infections progress to disease.These results are consistent with national surveillance of pulmonaryTB disease, and provide confidence that the analytical framework provides plausible results.