TUBERCULIN SKIN-TEST CONVERSION RATES IN NEW-YORK-CITY EMERGENCY MEDICAL-SERVICE HEALTH-CARE WORKERS

Objective: To determine annual tuberculin skin test conversion (infect ion) rates for prehospital health care workers (EMTs and paramedics) i n an urban environment with a high prevalence of Mycobacterium tubercu losis. Methods: We conducted a prospective study of prehospital health care workers for the New York City EMS, EMS Employee Health Service, and the Fire Department Bureau of Health Service to determine the tube rculin skin test conversion rates. In 1992, all current and new EMS pr ehospital health care workers without a known history of a positive tu berculin reaction received a baseline tuberculin purified protein deri vative (PPD) skin test. Thereafter, (January 1, 1993-December 31, 1996 ) all EMS health care workers who had negative PPD skin test results r eceived annual tuberculin PPD skin tests. Tuberculin skin test convers ion was defined as induration of 10 mm or greater in a worker with a d ocumented prior negative test result. The PPD skin test reaction was m easured by trained professional readers. Results: A total of 7,290 PPD test results were read during this study. Compliance with annual test ing was 75%. Annual tuberculin skin test conversion rates were 1.3% in 1993,.7% in 1994, .1% in '1995, and .2% in 1996 (average .5%). In a s tatic subgroup with at least 15 years' seniority, compliance with annu al testing was 100% and annual tuberculin skin test conversion rates w ere .5% in 1993, 0 in 1994, .5% in 1995, and 1.5% in 1996 (average .6% ). Conclusion: Despite the high prevalence of M tuberculosis infection in New York City and the potential for difficulty in the use of respi ratory precautions during emergency response operations, EMS prehospit al health care workers have an annual tuberculin conversion rate that is relatively low compared with hospital-based health care workers.