Nettleman and colleagues [1] presented concerns about the high costs of using particulate respirators in preventing transmission of tuberculosis (including multidrug-resistant tuberculosis) to health care workers exposed to patients with tuberculosis in health care facilities.

Despite infection control measures, some health care workers have already died from multidrug-resistant tuberculosis. As the number of cases of AIDS and multidrug-resistant tuberculosis increases, we expect to see more deaths among both immunosuppressed and immunocompetent health care workers. In this context, the effectiveness of high-efficiency particulate respirators certainly bears scrutiny. Neither the Centers for Disease Control and Prevention nor the National Institute for Occupational Health and Safety has recommended use of respirators alone; they are part of a comprehensive program that begins with minimizing the number of active cases by doing skin tests and by treating high-risk populations and that includes isolation, negative-pressure rooms, and other administrative and engineering controls in health care facilities. In our facility, I am aware of at least one purified protein derivative test conversion in an immunocompetent third-year medical student who was caring for a poorly compliant patient with multidrug-resistant tuberculosis. The patient was isolated in a negative-pressure room with ultraviolet lights; surgical masks were consistently used for respiratory protection.

Our Tuberculosis Task Force is working to provide optimal protection to all employees, with precautions including the use of high-efficiency respirators. Many—perhaps most—health care facilities have few cases of active tuberculosis, and thus the cost of preventive measures will be high in relation to the number of cases prevented. Further research and experience in the use of respirators to prevent tuberculosis may provide methods to save money without compromising protection. The use of particulate respirators currently seems a prudent and practical component to an overall program, despite its considerable expense.