Nosocomial tuberculosis prevention measures among two groups of US hospitals, 1992 to 1996

Objective: To compare trends in nosocomial tuberculosis (TB) prevention mea sures and health-care worker (HCW) tuberculin skin test (TST) conversion of hospitals with HIV-related Pneumocystis carinii pneumonia (PCP) patients a nd other US hospitals from 1992 through 1996, Design and setting: Surveys in 1992 and 1996 of 38 hospitals with PCP patie nts in four high-HIV-incidence cities and 136 other US hospitals from the A merican Hospital Association membership list. Participants: Twenty-seven hospitals with PCP patients and 103 other US hos pitals. Results: In 1992, 63% of PCP hospitals and other US hospitals had rooms mee ting Centers for Disease Control and Prevention (CDC) criteria tie, negativ e air pressure, six or more air exchanges per hour, and air directly vented to the outside) for acid-fast bacilli isolation; in 1996, almost 100% had such isolation rooms, Similarly, in 1992, nonfitted surgical masks were use d by HCWs at 60% of PCP hospitals and 68% at other US hospitals, while N95 respirators were used at 90% of PCP hospitals and 83% of other US hospitals in 1996, There was a significant decreasing trend in TST conversion rates among HCWs at both PCP and other US hospitals; however, this trend varied a mong all hospitals, HCWs at PCP hospitals had a higher risk of TST conversi on than those at other US hospitals (relative risk, 1.71; p < 0.0001). Conclusion: From 1992 through 1996, PCP and other US hospitals have made si milar improvements in their nosocomial TB prevention measures and decreased their HCW TST conversion rate. These data show that most hospitals are com pliant with CDC TB guidelines even before the enactment of an Occupational Safety and Health Administration TB standard.