This Article Full Text Full Text (PDF) Online Supplement All Versions of this Article: 200208-873BCv1 167/4/599    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Menzies, D. Articles by FitzGerald, J. M. Search for Related Content PubMed PubMed Citation Articles by Menzies, D. Articles by FitzGerald, J. M.

Factors Associated with Tuberculin Conversion in Canadian Microbiology and Pathology Workers

Department of Medicine, University of British Columbia, Vancouver, British Columbia; Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, Alberta; Department of Public Health Services, University of Toronto, Ontario; Departments of Medicine and Epidemiology and Biostatistics, Montreal Chest Institute, McGill University, Montreal, Quebec, Canada

Correspondence and requests for reprints should be addressed to Dick Menzies, M.Sc., M.D., Montreal Chest Institute, 3650, St. Urbain Street, Montreal, QC, H2X 2P4 Canada. E-mail: Dick.menzies{at}mcgill.ca

The risk of occupational tuberculosis (TB) infection and associated factors was estimated among all microbiology and pathology technicians and compared with a sample of nonclinical personnel in 17 Canadian acute care hospitals. Participants underwent tuberculin skin testing and completed questionnaires. Prior skin tests and vaccinations and all patients with TB hospitalized in the preceding 3 years were reviewed. Of the work areas where direction of air flow and air changes per hour were measured, only 51% were adequately ventilated. Among participating lab workers the average annual risk of tuberculin conversion was 1.0%. This was associated with lower hourly air exchange rates (16.7 versus 32.5 in workers with no conversion, p < 0.001) work in pathology (adjusted odds ratio [OR]: 5.4; [95% confidence interval: 1.3, 22], higher proportion of patients with missed diagnosis in the first 24 hours (per 20% increase—OR: 2.0; [1.3, 3.2], treatment delayed 1 week or more (per 20% increase—OR: 2.0; [3.2, 3.2]), and higher mortality (per 20% increase—OR: 2.5; [1.1, 5.6]). We conclude that laboratory workers, with no direct patient contact, have increased risk of tuberculin conversion in hospitals where a greater proportion of patients with TB die, or have delayed, or missed diagnosis, although this may be modified by workplace ventilation.

Key Words: tuberculosis • nosocomial transmission • occupational tuberculosis infection • autopsy • pathology and microbiology

This article has been cited by other articles:

				M. Pai, K. Gokhale, R. Joshi, S. Dogra, S. Kalantri, D. K. Mendiratta, P. Narang, C. L. Daley, R. M. Granich, G. H. Mazurek, et al. Mycobacterium tuberculosis Infection in Health Care Workers in Rural India: Comparison of a Whole-Blood Interferon {gamma} Assay With Tuberculin Skin Testing JAMA, June 8, 2005; 293(22): 2746 - 2755. [Abstract] [Full Text] [PDF]

				M. J. Tobin Tuberculosis, Lung Infections, Interstitial Lung Disease, Social Issues and Journalology in AJRCCM 2003 Am. J. Respir. Crit. Care Med., January 15, 2004; 169(2): 288 - 300. [Full Text] [PDF]