TUBERCULOSIS INFECTION AMONG HEALTH-CARE WORKERS IN MONTREAL

We conducted a cross-sectional survey to estimate the prevalence of tu berculosis infection among health care workers at two downtown Montrea l hospitals. Participants completed questionnaires, then underwent two -step tuberculin testing. Records of previous tuberculin tests and BCG vaccinations were reviewed. Charts of all tuberculosis patients admit ted in 1992-93 were also reviewed. Air changes and direction of air fl ow in patient care areas were measured using tracer gas techniques and smoke tubes. Of 619 eligible workers, 522 participated (84%). 196 (38 %) were tuberculin reactors; 23 (4%) had documented conversions. inade quate ventilation and delays in diagnosis were identified at both hosp itals. Comparing clinical with nonclinical personnel, the adjusted odd s of a significant initial tuberculin reaction were 2.6 (95% confidenc e interval 1.3, 5.2), of a documented conversion 13.6 (1.4, 132), and of a booster reaction 0.9 (0.2, 3.6). Initial tuberculin reactivity wa s associated with male gender (p = 0.008), BCG vaccination (p = 0.0001 ), foreign birth (p = 0.007), age (p < 0.0001), and occupation (p = 0. 02); conversion with male gender (p = 0.001) and occupation (p = 0.01) ; and boosting with older age (p = 0.02) and BCC vaccination (p = 0.00 1). Among clinical personnel at two hospitals, the prevalence of signi ficant tuberculin reactions and of documented conversions was unexpect edly high.