EVALUATING THE CONTROL OF TUBERCULOSIS AMONG HEALTH-CARE WORKERS - ADHERENCE TO CDC GUIDELINES OF 3 URBAN HOSPITALS IN CALIFORNIA

OBJECTIVE: To evaluate adherence to components of the Centers for Dise ase Control and Prevention (CDC) guidelines for preventing the transmi ssion of Mycobacterium tuberculosis in healthcare facilities. DESIGN: Multihospital study using direct observation and a standardized questi onnaire. SETTING: Three urban hospitals (two county hospitals and one private community hospital) in counties in California with a high numb er and incidence rate of tuberculosis (TB) cases. MEASUREMENTS: The ve ntilation performance of treatment and TB-patient isolation rooms was assessed. Questionnaire data regarding TB control policy and procedure s were obtained through interviews with the person(s) responsible for each program component; review of written TB control plans, training, and educational materials; and attendance at hospital TB control meeti ngs and trainings. RESULTS: Twenty-eight percent of isolation rooms te sted (7/25) were under positive pressure; 83% of rooms tested (20/24) had six or more nominal air changes per hour (ACH), but supply air did not mix rapidly with room air. Therefore, the nominal ACH likely over estimated the effective ACH and the subsequent protection provided. In virtually all rooms tested (26/27), air potentially containing M tube rculosis aerosol moved toward, rather than away from, likely worker lo cations. None of the hospitals regularly checked the performance of en gineering controls. Only one hospital adhered to the CDC minimum requi rements for respiratory protection. Training of healthcare workers gen erally was underutilized as a TB prevention measure. Hospitals did not provide comprehensive counseling regarding the need for healthcare wo rkers to know their immune status and the risks associated with M tube rculosis infection in an immunocompromised individual. Employee repres entatives did not have a voice in TB-related decision making. CONCLUSI ONS: Important aspects of day-to-day TB control practice did not confo rm to the written TB control policy. Subsequent to the identification of TB patients, healthcare workers at all three hospitals were potenti ally exposed to M tuberculosis aerosol due to breaches in negative-pre ssure isolation, the limitations of dilution ventilation, and the fail ure to maintain engineering controls and to implement respiratory prot ection controls fully. These findings lend support to the Occupational Safety and Health Administration's policy presumption that, absent cl ear evidence to the contrary, newly acquired healthcare-worker M tuber culosis infections are work-related.