SHEA-CDC TB SURVEY .2. EFFICACY OF TB INFECTION-CONTROL PROGRAMS AT MEMBER HOSPITALS, 1992

OBJECTIVE: To assess the efficacy of current Mycobacterium tuberculosi s control measures. DESIGN: Voluntary questionnaire to members of the Society for Healthcare Epidemiology of America. RESULTS: Healthcare wo rker (HCW) tuberculin skin-test (TST) conversion rates were significan tly higher in larger hospitals (greater than or equal to 437 beds) (0. 9% versus 0.6%; P<0.05), or in hospitals reporting greater than or equ al to 6 TB patients in 1992 (1.2% versus 0.6%; P<0.05). Among larger h ospitals or those hospitals surveyed reporting greater than or equal t o 6 TB patients, those without at least three of the four criteria sug gested in the 1990 Centers for Disease Control and Prevention (CDC) TB guidelines for acid-fast bacilli (AFB) isolation (specifically a sing le-patient room; negative pressure; and air exhausted directly outside ) had significantly higher annual TST conversion rates than those with these criteria (1.8% versus 0.6%; P<0.05). Respiratory therapist or b ronchoscopist TST conversion rates were significantly lower in hospita ls compliant with the exhaust criteria (1.2% versus 2.8%; P<0.05). Reg ardless of hospital characteristic, HCW TST conversion rates did not d iffer between hospitals in which HCWs used surgical masks or used disp osable particulate respirators. CONCLUSION: Among larger hospitals or hospitals reporting greater than or equal to 6 TB patients per year, f ailure to comply with the 1990 CDC TB recommendations for AFB isolatio n room guidelines was associated with higher HCW TST conversion rates. These data suggest that complete implementation of the 1990 CDC TB gu idelines would decrease HCWs' risk of nosocomial transmission of TB in larger hospitals or those reporting more TB patients. However, in non outbreak situations, disposable particulate respirators or submicron s urgical masks may not offer significantly greater protection to HCWs t han surgical masks