EVALUATION OF INFECTION-CONTROL MEASURES IN PREVENTING THE NOSOCOMIALTRANSMISSION OF MULTIDRUG-RESISTANT MYCOBACTERIUM-TUBERCULOSIS IN A NEW-YORK-CITY HOSPITAL

OBJECTIVE: To evaluate the efficacy of Centers for Disease Control and Prevention (CDC)-recommended infection control measures implemented i n response to an outbreak of multidrug-resistant (MDR) tuberculosis (T B). DESIGN: Retrospective cohort studies of acquired immunodeficiency syndrome (AIDS) patients and healthcare workers. The study period (Jan uary 1989 through September 1992) was divided into period I, before ch anges in infection control; period II, after aggressive use of adminis trative controls (eg, rapid placement of TB patients or suspected TB p atients in single-patient rooms); and period III, while engineering ch anges were made (eg, improving ventilation in TB isolation rooms). SET TING: A New York City hospital that was the site of one of the first r eported outbreaks of MDR-TB among AIDS patients in the United States. PARTICIPANTS: All AIDS patients admitted during periods I and II. Heal thcare workers on nine inpatient units with TB patients and six withou t TB patients. RESULTS: The epidemic (38 patients) waned during period II and only one MDR-TB patient presented during period III. The MDR-T B attack rate among AIDS patients hospitalized on the same ward on the same days as an infectious MDR-TB patient was 8.8% (19 of 216) during period I, decreasing to 2.6% (5 of 193; P=0.01) during period II. In a small group of healthcare workers with tuberculin skin test data, co nversions during periods II through III were higher on wards with than without TB patients (5 of 29 versus 0 of 15; P=0.15), although the di fference was not statistically significant. CONCLUSIONS: Transmission of MDR-TB among AIDS patients decreased markedly after enforcement of readily implementable administrative measures, ending the outbreak. Ho wever, tuberculin skin-test conversions among healthcare workers may n ot have been prevented by these measures. CDC guidelines for preventio n of nosocomial transmission of TB should be implemented fully at all US hospitals