Impact of Bordetella pertussis exposures on a Massachusetts tertiary care medical system.

OBJECTIVE: To assess the impact of outbreaks of Bordetella pertussis infection on a tertiary care medical system. DESIGN: Retrospective study. SETTING: Academic tertiary care medical center and affiliated ambulatory care settings. SUBJECTS: All patients and healthcare workers (HCWs) who were in close contact with patients with laboratory-confirmed cases of B. pertussis infection from October 1, 2003, through September 30, 2004. INTERVENTION: Direct and indirect medical center costs were determined, including low and high estimates of time expended in the evaluation and management of exposed patients and HCWs during outbreak investigations of laboratory-confirmed cases of B. pertussis infection. RESULTS: During this period, 20 primary and 3 secondary laboratory-confirmed cases of B. pertussis infection occurred, with 2 primary pertussis cases and 1 secondary case occurring in HCWs. Outbreak investigations prompted screening of 353 medical center employees. Probable or definitive exposure was identified for 296 HCWs, and 287 subsequently received treatment or prophylaxis for B. pertussis infection. Direct medical center costs for treatment and prophylaxis were $13,416 and costs for personnel time were $19,500-$31,190. Indirect medical center costs for time lost from work were $51,300-$52,300. The total cost of these investigations was estimated to be $85,066-$98,456. CONCLUSIONS: Frequent B. pertussis exposures had a major impact on our facility. Given the impact of exposures on healthcare institutions, routine vaccination for HCWs may be beneficial.

Impact of alcohol-based, waterless hand antiseptic on the incidence of infection and colonization with methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci.

OBJECTIVE: Colonized and infected inpatients are major reservoirs for methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), and transient carriage of these pathogens on the hands of healthcare workers remains the most common mechanism of patient-to-patient transmission. We hypothesized that use of alcohol-based, waterless hand antiseptic would lower the incidence of colonization and/or infection with MRSA and VRE. METHODS: On June 19, 2001, alcohol hand antiseptic was introduced at the University campus and not the nearby Memorial campus of the University of Massachusetts Medical School (Worcester, MA), allowing us to evaluate the impact of this antiseptic on the incidence of MRSA and VRE colonization and infection. From January 1 through December 31, 2001, the incidence of MRSA colonization or infection was compared between the 2 campuses before and after the hand antiseptic was introduced. Its effect on VRE colonization and infection was only studied in the medical intensive care unit at the University campus. RESULTS: At the University campus, the incidence of MRSA colonization or infection decreased from 1.26 cases/1,000 patient-days before the intervention to 0.75 cases/1,000 patient-days after the intervention, for a 1.46-fold decrease (95% confidence interval, 1.04-2.58; P = .037). At the Memorial campus, the incidence of MRSA colonization or infection remained virtually unchanged, from 0.34 cases/1,000 patient-days to 0.49 cases/1,000 patient-days during the same period. However, a separate analysis of the University campus data that controlled for proximity to prevalent cases did not show a significant improvement in the rates of infection or colonization. The incidence of nosocomial VRE colonization or infection before and after the hand antiseptic decreased from 12.0 cases/1,000 patient-days to 3.0 cases/1,000 patient-days, a 2.25-fold decrease (P = .018). Compliance with rectal surveillance for detection of VRE was 86% before and 84% after implementation of the hand antiseptic intervention. The prevalences of VRE cases during these 2 periods were 25% and 29%, respectively (P = .017). CONCLUSIONS: Alcohol hand antiseptic appears to be effective in controlling the transmission of VRE. However, after controlling for proximity to prevalent cases (ie, for clustering), it does not appear to be more effective than standard methods for controlling MRSA. Further controlled studies are needed to evaluate its effectiveness.

Rapid eradication of a cluster of Serratia marcescens in a neonatal intensive care unit: use of epidemiologic chromosome profiling by pulsed-field gel electrophoresis.

OBJECTIVE: To investigate a cluster of patients infected and colonized with Serratia marcescens in a neonatal intensive care unit (NICU). METHODS: In June 2001, two neonates in the NICU had clinical infections with S. marcescens and one died. Infection control surveillance data for the NICU revealed that S. marcescens was rarely isolated from clinical specimens. Surveillance and environmental cultures were performed and isolates were typed using pulsed-field gel electrophoresis. Staff and neonates were cohorted and a waterless, alcohol-based handwashing agent was introduced. A case-control study was performed. RESULTS: From June 2 through August 20, 2001, 11 neonates with S. marcescens infection and colonization were identified. The incidence of S. marcescens infections increased from 0.19 per 1,000 patient-days in 2000 to 0.52 per 1,000 patient-days in 2001 (P < .0001). In the first 3 weeks of the investigation, there were 2 sets of patients and sinks with indistinguishable strains; however, in subsequent weeks, all isolates were of unique strains, signifying no further transmission of the two initial predominant strains. Neonates with S. marcescens were more likely to have a lower gestational age and birth weight. There was no association between cases and healthcare workers (HCWs). CONCLUSIONS: A cluster of S. marcescens was quickly terminated after the introduction of preventive measures including cohorting of infected and colonized neonates and HCWs, contact precautions, surveillance cultures, and a waterless, alcohol-based hand antiseptic. Chromosomal typing determined that strains with an indistinguishable pattern were no longer present in the unit after control measures were implemented.

Impact of a program of intensive surveillance and interventions targeting ventilated patients in the reduction of ventilator-associated pneumonia and its cost-effectiveness.

OBJECTIVE: We hypothesized that a program of prospective intensive surveillance for ventilator-associated pneumonia (VAP) and concomitant implementations of multimodal, multidisciplinary preventive and intervention strategies would result in a reduction in the incidence of VAP and would be cost-effective. SETTING: Medical and surgical intensive care units (ICUs) in a university teaching hospital. INTERVENTIONS: All ventilated patients in the medical and surgical ICUs were monitored for VAP from January 1997 through December 1998. Interventions including elevation of the head of the bed, use of sterile water and replacement of stopcocks with enteral valves for nasogastric feeding tubes, and prolongation of changing of in-line suction catheters from 24 hours to as needed were implemented. RESULTS: The rates of VAP decreased by 10.8/1,000 ventilator-days in the medical ICU (CI95, 4.65-16.91) and by 17.2/1,000 ventilator-days in the surgical ICU (CI95, 2.85-31.56) when they were compared for 1997 and 1998. With the use of the estimated cost of a VAP of dollars 4,947 from the literature, the reduction resulted in cost savings of dollars 178,092 and dollars 148,410 in the medical and surgical ICUs, respectively, for a total of dollars 326,482. In addition, dollars 25,497 was saved due to the lengthening of the time for the change of in-line suction catheters, resulting in a cost savings of dollars 351,979. This total cost savings of dollars 351,979 minus the cost of enteral valves of dollars 2,100 resulted in total net savings of dollars 349,899. CONCLUSION: Intensive surveillance and interventions targeted at ventilated patients resulted in reduction of VAP and appeared to be cost-effective.

The changing epidemiology of vancomycin-resistant enterococci.

OBJECTIVE: To determine the distribution of vancomycin-resistant enterococci (VRE) cases in our hospital and those from outside of our hospital from 1993 through 1998. METHODS: Weekly rectal surveillance was instituted whenever there were two or more cases present in the units. Cases were divided into acquired in our hospital, acquired outside of our hospital (VRE positive after and within 72 hours of admission, respectively), and indeterminate. Hospital cases were attributed to the originating ward or intensive care unit (ICU) if patients were noted to be positive within 72 hours of transfer. RESULTS: From 1993 to 1998, the rate of VRE per 1,000 admissions increased threefold, from 3.2 to 9.8, for the hospital. VRE cases acquired outside of the hospital increased by approximately 5% per year (r = 0.87; P = .03). The rate of VRE per 1,000 admissions increased 1.7-fold in the ICUs and 3.6-fold in the wards. The ICUs had an average of 75.3 cases per year, with the number of new cases per year increasing by approximately 9 (r = 0.80; P = .028). In the wards, there were an average of 22.0 new cases per year, with a slight upward trend of 3 additional new cases per year (r = 0.69; P = .64). There was a highly significant increasing linear trend (P = .0007) for VRE colonization and infection. CONCLUSION: Although VRE still predominate in the ICUs, cases originating from outside of our hospital and the wards are becoming more common. VRE colonization remained more frequent than infection.

Use of silver-hydrogel urinary catheters on the incidence of catheter-associated urinary tract infections in hospitalized patients.

BACKGROUND: Urinary tract infections (UTIs) account for 40% of all nosocomial infections, and about 80% of these are associated with the use of urinary catheters. They not only contribute to excess morbidity and mortality, but they also significantly add to the cost of hospitalization. Clinical trials with silver-coated urinary catheters have shown conflicting results. However, recent trials with silver-hydrogel urinary catheters have shown a reduction in nosocomial UTIs, and these catheters appear to offer cost savings. METHOD: The University of Massachusetts Medical Center is a teaching, tertiary hospital with 18% of its beds in intensive care units. The silver-hydrogel urinary catheters were introduced in October 1997. The rate of catheter-associated UTIs with silver-hydrogel urinary catheter use was compared with a historical baseline UTI rate that was established for January 1996 and January 1997 with the standard, noncoated catheters. The cost of a nosocomial catheter-associated UTI was estimated by calculating the hospital charges resulting from all urinary catheter-associated UTIs in 1 month. A cost-analysis of silver-hydrogel urinary catheter use was performed. RESULTS: The rate of catheter-associated UTIs for noncoated catheters was 4.9/1000 patient-days compared with 2.7/1000 patient-days for the silver-hydrogel catheters, a reduction of 45% (P =.1). The average cost (calculated with hospital charges) of a catheter-associated UTI at our institution was estimated to be $1214.42 US dollars, with a median of $613.72 US dollars. The estimated cost-saving ranged from $12,563.52 US dollars to $142,314.72 US dollars. CONCLUSIONS: The use of silver-hydrogel urinary catheters resulted in a nonsignificant reduction in catheter-associated UTIs and a modest cost-saving.