Comparison of Tuberculosis Infection Control Programs in Canadian Hospitals Categorized by Size and Risk of Exposure to Tuberculosis Patients, 1989 to 1993 – Part 2

Abstract

OBJECTIVE: To analyze tuberculosis (TB) programs in acute care hospitals (hospitals) categorized by size and risk of exposure to TB patients from 1989 to 1993.DESIGN: Retrospective survey.PARTICIPANTS: Members of the Community and Hospital Infection Control Association-Canada and l’Association des professionnels pour la prévention des infections who worked in Canadian hospitals received questionnaires. One questionnaire per hospital was completed.OUTCOME: Hospitals reported the number of respiratory TB and human immunodeficiency virus (HIV) cases admitted, the engineering and environmental controls available, and the type of occupational TB screening programs available. Data were stratified by hospital size and risk of exposure to TB patients.RESULTS: Thirty-four (10.9%) hospitals with at least 500 beds admitted more than 50% of the TB cases, more than 40% of the multidrug-resistant TB (MDR-TB) cases and more than 65% of the HIV cases. Thirty-six (11.6%) facilities classified as high risk hospitals reported more than 70% of the TB cases, more than 58% of the MDR-TB cases and more than 75% of the HIV cases. A significantly higher pooled average tuberculin test conversion rate was found in individuals working in high risk (4.4%) than in low risk hospitals (1.5%). Significantly more high risk than low risk hospitals had an isolation room with air exhausted outside, negative air pressure and at least six air changes per hour. Only 13 high risk hospitals had all three engineering characteristics. Surgical masks were used for respiratory protection in 18 (50%) high risk and 186 (77.8%) low risk hospitals.CONCLUSIONS: Nosocomial transmission of Mycobacterium tuberculosis may have occurred because TB programs available in many Canadian hospitals were inadequate.