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; CI95, 1.7-19.2; P < .01). HCWs not born in the United States and those employed at the Office of the Chief Medical Examiner (OCME) were at high risk for baseline tuberculin positivity (OR, 3.2; CI95, 1.7-5.8; P < .001); OCME HCWs (OR, 4.7; CI95, 2.3-9.4; P < .001), those of Asian ethnicity (OR, 4.3; CI95, 1.4-13.5; P < .01), and older HCWs (OR, 1.0; CI95, 1.0-1.1; P < .05) were at a higher risk for conversion.

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.