Clostridium difficile spores persist in hospital environments for an extended period. We evaluated whether admission to a room previously occupied by a patient with C. difficile infection (CDI) increased the risk of acquiring CDI.

Retrospective cohort study.

Medical intensive care unit (ICU) at a tertiary care hospital.

Patients admitted from January 1, 2005, through June 30, 2006, were evaluated for a diagnosis of CDI 48 hours after ICU admission and within 30 days after ICU discharge. Medical, ICU, and pharmacy records were reviewed for other CDI risk factors. Admitted patients who did develop CDI were compared with admitted patients who did not.

Among 1,844 patients admitted to the ICU, 134 CDI cases were identified. After exclusions, 1,770 admitted patients remained for analysis. Of the patients who acquired CDI after admission to the ICU, 4.6% had a prior occupant without CDI, whereas 11.0% had a prior occupant with CDI (P = .002). The effect of room on CDI acquisition remained a significant risk factor (P = .008) when Kaplan-Meier curves were used. The prior occupant's CDI status remained significant (P = .01; hazard ratio, 2.35) when controlling for the current patient's age, Acute Physiology and Chronic Health Evaluation III score, exposure to proton pump inhibitors, and antibiotic use.

A prior room occupant with CDI is a significant risk factor for CDI acquisition, independent of established CDI risk factors. These findings have implications for room placement and hospital design.

To report a large outbreak of Clostridium difficile infection (CDI; ribotype 027) between June 2007 and August 2008, describe infection control measures, and evaluate the impact of restricting the use of fluoroquinolones in controlling the outbreak.

Outbreak investigation in 3 acute care hospitals of the Northern Health and Social Care Trust in Northern Ireland.

Implementation of a series of CDI control measures that targeted high-risk antibiotic agents (ie, restriction of fluoroquinolones), infection control practices, and environmental hygiene.

A total of 318 cases of CDI were identified during the outbreak, which was the result of the interaction between C. difficile ribotype 027 being introduced into the affected hospitals for the first time and other predisposing risk factors (ranging from host factors to suboptimal compliance with antibiotic guidelines and infection control policies). The 30-day all-cause mortality rate was 24.5%; however, CDI was the attributable cause of death for only 2.5% of the infected patients. Time series analysis showed that restricting the use of fluoroquinolones was associated with a significant reduction in the incidence of CDI (coefficient, —0.054; lag time, 4 months; P = .003).

These findings provide additional evidence to support the value of antimicrobial stewardship as an essential element of multifaceted interventions to control CDI outbreaks. The present CDI outbreak was ended following the implementation of an action plan improving communication, antibiotic stewardship, infection control practices, environmental hygiene, and surveillance.

To compare 8 severity score indices for Clostridium difficile infection (CDI).

Prospective observational study.

This study was conducted from July through October 2006. All hospitalized patients in 3 university-affiliated hospitals with a positive fecal Clostridium difficile toxin assay result were evaluated. Infection was considered severe if patients had at least 1 of the following clinical events during their hospitalization: (1) death attributed to CDI within 30 days after diagnosis, (2) colectomy necessitated by CDI, or (3) intensive care unit admission for management of complications attributed to CDI. Severity was assessed on the basis of 8 severity score indices, using published criteria for severe CDI as the benchmark. The 8 severity score indices studied were Beth Israel, University of Pittsburgh Medical Center version 1, University of Pittsburgh Medical Center version 2, Hines VA, modified University of Illinois, University of Calgary version 1, University of Calgary version 2, and University of Temple.

Of 184 patients with CDI evaluated, 19 had severe cases and 165 had nonsevere cases, as assessed on the basis of the defined severe CDI criteria. Sensitivities of the 8 severity score indices studied ranged from 63.2% to 84.2%, and specificities ranged from 59.4% to 93.9%. The Hines VA index had the highest kappa score (0.69 [95% confidence interval, 0.54-0.83]), followed by the University of Pittsburgh Medical Center version 1 index. Independent risk factors for severe CDI determined by multivariate analysis were abdominal distention (P = .007), fever (temperature, 38.0°C or above; P = .042), white blood cell count of at least 20,000 cells/mm3 (P = .035), and hypoalbuminemia (serum albumin level less than 3 mg/dL; P = .029).

The Hines VA CDI severity score index appeared to display the strongest correlation for predicting more severe forms of CDI.

Nosocomial outbreaks of norovirus infection pose a great challenge to the infection control team.

Between November 1, 2009, and February 28, 2010, strategic infection control measures were implemented in a hospital network. In addition to timely staff education and promotion of directly observed hand hygiene, reverse-transcription polymerase chain reaction for norovirus was performed as an added test by the microbiology laboratory for all fecal specimens irrespective of the request for testing. Laboratory-confirmed cases were followed up by the infection control team for timely intervention. The incidence of hospital-acquired norovirus infection per 1,000 potentially infectious patient-days was compared with the corresponding period in the preceding 12 months, and the incidence in the other 6 hospital networks in Hong Kong was chosen as the concurrent control. Phylogenetic analysis of norovirus isolates was performed.

Of the 988 patients who were tested, 242 (25%) were positive for norovirus; 114 (47%) of those 242 patients had norovirus detected by our added test. Compared with the corresponding period in the preceding 12 months, the incidence of hospital-acquired norovirus infection decreased from 131 to 16 cases per 1,000 potentially infectious patient-days (P < .001 ), although the number of hospital-acquired infections was low in both the study period (n = 8) and the historical control periods (n = 11). The incidence of hospital-acquired norovirus infection in our hospital network (0.03 cases per 1,000 patient-days) was significantly lower than that of the concurrent control (0.06 cases per 1,000 patient-days) (P = .015). Forty-three (93%) of 46 norovirus isolates sequenced belonged to the genogroup II.4 variant.

Strategic infection control measures with an added test maybe useful in controlling nosocomial transmission of norovirus.

A paucity of data exists regarding the effectiveness of daily Chlorhexidine gluconate (CHG) bathing in non–intensive care unit (ICU) settings.

To evaluate the effectiveness of daily CHG bathing in a non-ICU setting to reduce methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enteroccocus (VRE) hospital-acquired infections (HAIs), compared with daily bathing with soap and water.

Quasi-experimental study design; the primary outcome was the composite incidence of MRSA and VRE HAIs. Clostridium difficile HAI incidence was measured as a nonequivalent dependent variable with which to assess potential confounders.

Four general medicine units, with a total of 94 beds, at a 719-bed academic tertiary-care facility in Providence, Rhode Island.

A total of 7,102 and 7,699 adult patients were admitted to the medical service in the control and intervention groups, respectively. Patients admitted from January 1 through December 31, 2008, were bathed daily with soap and water (control group), and those admitted from February 1, 2009, through March 31, 2010, were bathed daily with CHG-impregnated cloths (intervention group).

Daily bathing with CHG was associated with a 64% reduced risk of developing the primary outcome, namely, the composite incidence of MRSA and VRE HAIs (hazard ratio, 0.36 [95% CI, 0.2-0.8]; P = .01). There was no change in the incidence of C. difficile HAIs (P = .6). Colonization with MRSA was associated with an increased risk of developing a MRSA HAI (hazard ratio, 8 [95% CI, 3-19]; P < .001).

Daily CHG bathing was associated with a reduced HAI risk, using a composite endpoint of MRSA and VRE HAIs, in a general medical inpatient population.

To assess risk factors for methicillin-resistant Staphylococcus aureus (MRSA) acquisition among extended care residents focusing on level of care (residential vs rehabilitation) and room placement with an MRSA-positive resident.

Prospective cohort study.

Extended care units at 2 healthcare systems in Maryland.

Four hundred forty-three residents with no history of MRSA and negative MRSA surveillance cultures of the anterior nares and areas of skin breakdown at enrollment.

Follow-up cultures were collected every 4 weeks and/or at discharge for a period of 12 weeks. Study data were collected by a research nurse from the medical staff and the electronic medical records. Cox proportional hazards modeling was used to calculate adjusted hazards ratios (aHRs) and 95% confidence intervals (CIs).

Residents in rehabilitation care had 4-fold higher risk of MRSA acquisition compared with residents in residential care (hazard ratio [HR], 4. [95% CI, 2.2-8.8]). Being bedbound was significantly associated with MRSA acquisition in both populations (residential care, aHR, 4.3 [95% CI, 1.5-12.2]; rehabilitation care, aHR, 4.8 [95% CI, 1.2-18.7]). Having an MRSA-positive roommate was not significantly associated with acquisition in either population (residential care, aHR, 1.4 [95% CI, 0.5-3.9]; rehabilitation care, aHR, 0.5 [95% CI, 0.1-2.2]); based on concordant spa typing, only 2 of 8 residents who acquired MRSA and had room placement with an MRSA-positive resident acquired their MRSA isolate from their roommate.

Residents in rehabilitation care appear at higher risk and have different risk factors for MRSA acquisition compared to those in residential care.

To compare the impacts of different methicillin-resistant Staphylococcus aureus (MRSA) screening test options (eg, polymerase chain reaction [PCR], rapid culture) and program characteristics on the clinical outcomes and budget of a typical US hospital.

We developed an Excel-based decision-analytic model, using published literature to calculate and compare hospital costs and MRSA infection rates for PCR- or culture-based MRSA screening and then used multivariate sensitivity analysis to evaluate key variables. Same-day PCR testing for a representative 370-bed teaching hospital in the United States was assessed in different populations (high-risk patients, intensive care unit [ICU] patients, or all patients) and compared with other test options.

Different screening program populations (all patients, high-risk patients, ICU patients, or patients with previous MRSA colonization or infection only) represented a potential savings of $12,158-$76,624 per month over no program ($188,618). Analysis of multiple test options in high-risk population screening indicated that same-day PCR testing of high-risk patients resulted in fewer infections over 1,720 patient-days (2.9, compared with 3.5 for culture on selective media and 3.8 for culture on nonselective media) and the lowest total cost ($112,012). The costs of other testing approaches ranged from $113,742 to $123,065. Sensitivity analysis revealed that variations in transmission rate, conversion to infection, prevalence increases, and hospital size are important to determine program impact. Among test characteristics, turnaround time is highly influential.

All screening options showed reductions in infection rates and cost impact improvement over no screening program. Among the options, same-day PCR testing for high-risk patients slightly edges out the others in terms of fewest infections and greatest potential cost savings.

To identify the prevalence and risk factors for complications associated with percutaneously inserted central venous catheters (PICCs) and evaluate the effect of different catheter types and their indwelling time on catheter-related complications.

Retrospective cohort study.

A 49-bed neonatal intensive-care teaching hospital in Taiwan.

Between 2004 and 2007, 518 single-lumen PICCs (defined as “old type”) and 290 PICCs with a stiffening stylet and a thicker introducer (“new type”) were inserted in a total of 534 neonates with a birth body weight of 1,500 g or less.

Independent risk factors of catheter-related sepsis (CRS) were longer duration for PICC placement and PICC inserted at femoral site (compared with nonfemoral sites) (odds ratio [OR], 1.53 [95% confidence interval {CI}, 1.07-2.25]; P = .044). An independent predictor of catheter-related noninfectious complications was time spent for PICC insertion of more than 60 minutes (compared with less than 30 minutes) (OR, 1.96 [95% CI, 1.08-3.53]; P = .026). New-type PICCs were significantly associated with a higher rate of femoral site insertion, catheter-related noninfectious complications, and longer time for successful insertion than old-type PICCs. The hazard rates of CRS according to indwelling time, determined over 5-day periods by survival analysis, showed 0.05% for catheters in place for 4 days or less; 0.27% for 5-9 days; 0.40% for 10-14 days; 0.68% for 15-19 days; 1.18% for 20-24 days; 3.96% for 25-29 days; and 10.45% for 30 or more days.

Different catheters do influence the complication rates. Spending more than 60 minutes for successful PICC insertion and PICCs indwelling for more than 30 days are associated with higher rates of catheter-related complications.

To describe outbreaks of nosocomial influenza infection with molecular methods and to elucidate the viral linkages among outbreak case patients including both inpatients and healthcare workers (HCWs).

A 180-bed acute and long-term care hospital in Japan.

Retrospective observational study of nosocomial outbreaks of infection with influenza A/H3N2. Together with information about onset dates and vaccination history, we obtained nasopharyngeal swab samples from individuals with cases of influenza or influenzalike illness (ILI). The hemagglutinin genes of the recovered viruses were sequenced and compared, along with those of community-circulating strains, for similarity by phylogenetic tree analysis.

The outbreaks occurred from February 26 through April 3, 2007, during the 2006–2007 epidemic season, and they involved 11 patients and 13 HCWs. The 2 outbreaks involved 2 different genotypes of influenza A/H3N2 viruses. These virus variants were closely related to the influenza strains that were circulating in the community during the same epidemic season.

This study showed the dissemination of highly homologous influenza virus variants among inpatients and HCWs within a short period, as a result of nosocomial transmission. These strains were also similar to influenza strains that were circulating in the community.

The standardized infection ratio (SIR) is an indirectly standardized morbidity ratio that has been used to compare the infection rate in a hospital with an expected number of infections from a national standard and is being increasingly promoted as a metric for the public reporting of healthcare-associated infections (HAIs).

To identify potential discrepancies between SIR and other measures of risk.

Hypothetical and real data were compared using relative risk, a directly standardized morbidity ratio, and SIR values across a range of varying hospital population compositions.

In real and hypothetical data, other summary statistics were consistent with each other and with underlying HAI incidence density rates. However, use of the SIR frequently led to conclusions inconsistent with these other inherently unbiased estimators.

Because of a recognized type of distortion inherent in the calculation of indirectly standardized ratios, use of the SIR can lead to conclusions that differ from those reached when using other traditional measures of risk and to incorrect assessments of conclusions about the performance of hospitals or states. In addition, the tendency to inappropriately arrange SIR values in rank order for comparison makes SIR unsuitable as a statewide metric for monitoring HAIs.