Prevalence of tuberculin skin test positivity and conversions among healthcare workers in New York City during 1994 to 2001.

Objective: To determine the prevalence of and risk factors for tuberculin skin test positivity and conversion among New York City Department of Health and Mental Hygiene employees. Design: Point-prevalence survey and prospective cohort analysis. Sentinel surveillance was conducted from March 1,1994, to December 31, 2001. Participants: HCWs in high-risk and low-risk settings for occupational TB exposure. Results: Baseline tuberculin positivity was 36.2% (600 of 1,658), 15.5% (143 of 922) among HCWs born in the United States, and 48.5% (182 of 375) among HCWs not born in the United States. There were 36 tuberculin conversions during 2,754 observation-years (rate, 1.3 per 100 person-years). For HCWs born in the United States, the risk for tuberculin conversion was greater in high-risk occupational settings compared with low-risk settings (OR 5.7; CI 95 , 1.7–19.2; P 95 ,1.7–5.8; P 95 , 2.3–9.4; P 95 ,1.4–13.5; P 95 ,1.0–1.1; p Conclusions: Although the prevalence of tuberculin positivity decreased after the peak of the recent TB epidemic in New York City, the conversion rate among HCWs in high-risk occupational settings for TB exposure was still greater than that among HCWs in low-risk settings. Continued surveillance of occupational TB infection is needed, especially among high-risk HCWs.