In Pennsylvania, reporting of healthcare-associated infections (HAIs) was mandated in 2007, and hospitals were encouraged to implement qualified electronic surveillance (QES) systems to assist HAI detection. This study evaluated the usefulness of these systems in reducing HAIs.

Online survey and retrospective cohort study. Eligible facilities had a QES or manual system in place for the entire study period and sufficient data in selected hospital units.

Surveys were sent to infection preventionists (IPs) in all Pennsylvania hospitals to gather qualitative information about their systems. National Healthcare Safety Network data from Pennsylvania hospitals for July 2008 through June 2010 were used to compare catheter-associated urinary tract infection (CAUTI) rates in facilities with and without a QES system.

IPs from 174 facilities responded to the survey. Data from 119 of 234 hospitals were analyzed.

IPs in facilities with a QES system reported spending as much time on data management and education as IPs in hospitals with manual surveillance. Significant interaction was observed in CAUTI rates over time between groups of facilities with and without a QES system after controlling for device-utilization ratio, location within hospital, and licensed bed size (P< .01). QES hospitals showed a significant decline in CAUTI rates (P< .01); manual surveillance facilities showed no change in rates (P> .05).

Over the 2-year period, a significant decline in CAUTI rates was observed in facilities with a QES system. This suggests that electronic systems may aid in reducing HAI rates. Additional data are needed to see whether these improvements and trends persist.

Infect Control Hosp Epidemiol 2012;33(2):105-111

Hospitalized patients are at increased risk for acquisition of methicillin-resistant Staphylococcus aureus (MRSA). As hospital length of stay shortens, hospital-acquired MRSA events may be more likely to be detected after discharge.

We assessed the impact of attributing MRSA cases discovered within 30 days after discharge to the most recent hospitalization and identified patient characteristics associated with MRSA detection after discharge.

Retrospective cohort study.

Twenty-seven acute care hospitals in Orange County, California.

Adult acute care admissions (2002–2007).

Using a countywide hospital data set containing diagnostic codes with present-on-admission (POA) indicators, we identified the first admission with a MRSA code for each patient. This incident MRSA admission was defined as predischarge-detected (pre-DD) hospital-onset MRSA (HO-MRSA) when MRSA was not POA. If MRSA was POA and a prior admission occurred within 30 days, this prior admission was assigned postdischarge-detected (post-DD) HO-MRSA. We evaluated the impact of including post-DD HO-MRSA in the calculation of hospital HO-MRSA incidence using signed-rank tests and reviewed changes in hospital rankings. We conducted multivariate comparisons of patient characteristics of pre-DD versus post-DD HO-MRSA patients.

Among 1,217,253 at-risk hospitalizations, the inclusion of post-DD HO-MRSA tripled the median hospital HO-MRSA incidence, from 12.2 to 35.7 cases per 10,000 at-risk admissions (P<.0001). Hospital ranking changed substantially when including post-DD HO-MRSA. Patients with shorter stays were more likely to have post-DD MRSA.

On the basis of administrative claims data, the inclusion of post-DD HO-MRSA significantly increased the estimated HO-MRSA incidence and altered hospital rankings. This finding underscores the limitations of single-facility data when deriving HO-MRSA incidence and rank.

Infect Control Hosp Epidemiol 2012;33(2):114-121

To assess the benefit of using procedure-specific alternative cutoff points for National Nosocomial Infections Surveillance (NNIS) risk index variables and of extending surgical site infection (SSI) risk prediction models with a postdischarge surveillance indicator.

Open, retrospective, validation cohort study.

Five private, nonuniversity Brazilian hospitals.

Consecutive inpatients operated on between January 1993 and May 2006 (other operations of the genitourinary system [n = 20,723], integumentary system [n = 12,408], or musculoskeletal system [n = 15,714] and abdominal hysterectomy [n = 11,847]).

For each procedure category, development and validation samples were defined nonrandomly. In the development samples, alternative SSI prognostic scores were constructed using logistic regression: (i) alternative NNIS scores used NNIS risk index covariates and cutoff points but locally derived SSI risk strata and rates, (ii) revised scores used procedure-specific alternative cutoff points, and (iii) extended scores expanded revised scores with a postdischarge surveillance indicator. Performances were compared in the validation samples using calibration, discrimination, and overall performance measures.

The NNIS risk index showed low discrimination, inadequate calibration, and predictions with high variability. The most consistent advantage of alternative NNIS scores was regarding calibration (prevalence and dispersion components). Revised scores performed slightly better than the NNIS risk index for most procedures and measures, mainly in calibration. Extended scores clearly performed better than the NNIS risk index, irrespective of the measure or operative procedure.

Locally derived SSI risk strata and rates improved the NNIS risk index's calibration. Alternative cutoff points further improved the specification of the intrinsic SSI risk component. Controlling for incomplete postdischarge SSI surveillance provided consistently more accurate SSI risk adjustment.

Infect Control Hosp Epidemiol 2012;33(2):124-134

Little is known about how hospital organizational and cultural factors associated with implementation of quality initiatives such as the Institute for Healthcare Improvement's (IHI) 100,000 Lives Campaign differ among levels of healthcare staff.

Evaluation of a mixed qualitative and quantitative methodology (“trilogic evaluation model”).

Six hospitals that joined the campaign before June 2006.

Three strata of staff (executive leadership, midlevel, and frontline) at each hospital.

Surveys were completed in 2008 by 135 hospital personnel (midlevel, 43.7%; frontline, 38.5%; executive, 17.8%) who also participated in 20 focus groups. Overall, 93% of participants were aware of the IHI campaign in their hospital and perceived that 58% (standard deviation, 22.7%) of improvements in quality at their hospital were a direct result of the campaign. There were significant differences between staff levels on the organizational culture (OC) items, with executive-level staff having higher scores than midlevel and frontline staff. All 20 focus groups perceived that the campaign interventions were sustainable and that data feedback, buy-in, hardwiring (into daily activities), and leadership support were essential to sustainability.

The trilogic model demonstrated that the 3 levels of staff had markedly different perceptions regarding the IHI campaign and OC. A framework in which frontline, midlevel, and leadership staff are simultaneously assessed may be a useful tool for future evaluations of OC and quality initiatives such as the IHI campaign.

Infect Control Hosp Epidemiol 2012;33(2):135-143

Healthcare-associated infections (HAIs) result in significant morbidity and mortality. Hand hygiene remains a cornerstone intervention for preventing HAIs. Unfortunately, adherence to hand hygiene guidelines among healthcare personnel is poor.

To assess short- and long-term effects of an infection prevention promotion program on healthcare personnel hand hygiene behaviors.

Time series design.

Our study was conducted at a tertiary care academic center.

Hospital healthcare personnel.

We developed a multimodal program that included a multimedia communications campaign, education, leadership engagement, environment modification, team performance measurement, and feedback. Healthcare personnel hand hygiene practices were measured via direct observations over a 3-year period by “undercover” observers.

Overall hand hygiene compliance increased by 2-fold after full program implementation (P<.001), and this increase was sustained over a 20-month follow-up period (P< .001). The odds for compliance with hand hygiene increased by 3.8-fold in the 6 months after full program implementation (95% confidence interval, 3.53–4.23; P< .001), and this increase was sustained. There was even a modest increase at 20 months of follow up. Hand hygiene compliance increased among all disciplines and hospital units. Hand hygiene compliance increased from 35% in the first 6 months after program initiation to 77% in the last 6 months of the study period among nursing providers (P<.001), from 38% to 62% among medical providers (P<.001), and from 27% to 75% among environmental services staff (P<.001).

Implementation of the infection prevention promotion program was associated with a significant and sustained increase in hand hygiene practices among healthcare personnel of various disciplines.

Infect Control Hosp Epidemiol 2012;33(2):144-151

To perform a cost-effectiveness analysis to evaluate preoperative use of mupirocin in patients with total joint arthroplasty (TJA).

Simple decision tree model.

Outpatient TJA clinical setting.

Hypothetical cohort of patients with TJA.

A simple decision tree model compared 3 strategies in a hypothetical cohort of patients with TJA: (1) obtaining preoperative screening cultures for all patients, followed by administration of mupirocin to patients with cultures positive for Staphylococcus aureus; (2) providing empirical preoperative treatment with mupirocin for all patients without screening; and (3) providing no preoperative treatment or screening. We assessed the costs and benefits over a 1-year period. Data inputs were obtained from a literature review and from our institution's internal data. Utilities were measured in quality-adjusted life-years, and costs were measured in 2005 US dollars.

Incremental cost-effectiveness ratio.

The treat-all and screen-and-treat strategies both had lower costs and greater benefits, compared with the no-treatment strategy. Sensitivity analysis revealed that this result is stable even if the cost of mupirocin was over $100 and the cost of SSI ranged between $26,000 and $250,000. Treating all patients remains the best strategy when the prevalence of S. aureus carriers and surgical site infection is varied across plausible values as well as when the prevalence of mupirocin-resistant strains is high.

Empirical treatment with mupirocin ointment or use of a screen-and-treat strategy before TJA is performed is a simple, safe, and cost-effective intervention that can reduce the risk of SSI. S. aureus decolonization with nasal mupirocin for patients undergoing TJA should be considered.

Level II, economic and decision analysis.

Infect Control Hosp Epidemiol 2012;33(2):152-159

Staphylococcus aureus is a cause of community- and healthcare-acquired infections and is associated with substantial morbidity, mortality, and costs. Vancomycin minimum inhibitory concentrations (MICs) among S. aureus have increased, and reduced vancomycin susceptibility (RVS) may be associated with treatment failure. We aimed to identify clinical risk factors for RVS in S. aureus bacteremia.

Case-control.

Academic tertiary care medical center and affiliated urban community hospital.

Cases were patients with RVS S. aureus isolates (defined as vancomycin E-test MIC >1.0 μg/mL). Controls were patients with non-RVS S. aureus isolates.

Of 392 subjects, 134 (34.2%) had RVS. Fifty-eight of 202 patients (28.7%) with methicillin-susceptible S. aureus (MSSA) isolates had RVS, and 76 of 190 patients (40.0%) with methicillin-resistant S. aureus (MRSA) isolates had RVS (P = .02). In unadjusted analyses, prior vancomycin use was associated with RVS (odds ratio [OR], 2.08; 95% confidence interval [CI], 1.00–4.32; P = .046). In stratified analyses, there was significant effect modification by methicillin susceptibility on the association between vancomycin use and RVS (P = .04). In multivariate analyses, after hospital of admission and prior levofloxacin use were controlled for, the association between vancomycin use and RVS was significant for patients with MSSA infection (adjusted OR, 4.02; 95% CI, 1.11–14.50) but not MRSA infection (adjusted OR, 0.87; 95% CI, 0.36–2.13).

A substantial proportion of patients with S. aureus bacteremia had RVS. The association between prior vancomycin use and RVS was significant for patients with MSSA infection but not MRSA infection, suggesting a complex relationship between the clinical and molecular epidemiology of RVS in S. aureus.

Infect Control Hosp Epidemiol 2012;33(2):160-166

The emergence of Staphylococcus aureus with reduced susceptibility to glycopeptides (glycopeptide-intermediate S. aureus [GISA] and heterogeneous GISA [h-GISA]) leads to intensive care unit (ICU) outbreaks that frequently result in ward closure. We investigated the role of hospital hygiene in the transmission and eradication of an h-GISA outbreak.

The study is a description of an original environmental investigation around a series of 12 cases.

The outbreak occurred in a 20-bed polyvalent/trauma ICU in a 2,800-bed tertiary care university hospital in France.

Specimens were obtained for surveillance and diagnostic cultures from all patients in the unit. Surface sampling was also performed. Geographic cohorting, contact isolation, emphasis on adherence to infection control practices, and environmental cleaning were implemented.

Twelve patients with h-GISA infection (n = 5) or colonization (n = 7) were identified. The mean interval between admission and h-GISA detection was 23.6 days (range, 10–89 days), with a median of 16.5 days. Environmental investigation identified an unexpected reservoir, namely, SpO2 sensors. The outbreak was controlled by a combination of measures, including eradication of this reservoir, avoiding total ward closure.

Targeted surface sampling helps to secure the environment through active investigation of various reservoirs while maintaining normal activity on the ward. In our study, this method led to the detection of an unsuspected reservoir, the eradication of which helped control the h-GISA epidemic. Further applications of this original investigative procedure should allow confirmation of its relevance and efficiency.

Infect Control Hosp Epidemiol 2012;33(2):167-174

To determine the frequency of false-positive Clostridium difficile toxin enzyme immunoassay (EIA) results in hospitalized children and to examine potential reasons for this false positivity.

Nested case-control.

Two tertiary care pediatric hospitals.

As part of a natural history study, prospectively collected EIA-positive stools were cultured for toxigenic C. difficile, and characteristics of children with false-positive and true-positive EIA results were compared. EIA-positive/culture-negative samples were recultured after dilution and enrichment steps, were evaluated for presence of the tcdB gene by polymerase chain reaction (PCR), and were further cultured for Clostridium sordellii, a cause of false-positive EIA toxin assays.

Of 112 EIA-positive stools cultured, 72 grew toxigenic C. difficile and 40 did not, indicating a positive predictive value of 64% in this population. The estimated prevalence of C. difficile infection (CDI) in the study sites among children tested for this pathogen was 5%–7%. Children with false-positive EIA results were significantly younger than those with true-positive tests but did not differ in other characteristics. No false-positive specimens yielded C. difficile when cultured after enrichment or serial dilution, 1 specimen was positive for tcdB by PCR, and none grew C. sordellii.

Approximately one-third of EIA tests used to evaluate pediatric inpatients for CDI were falsely positive. This finding was likely due to the low prevalence of CDI in pediatric hospitals, which diminishes the test's positive predictive value. These data raise concerns about the use of EIA assays to diagnosis CDI in children.

Infect Control Hosp Epidemiol 2012;33(2):175-179

To define the extent of an outbreak of Achromobacter xylosoxidans bacteremia, determine the source of the outbreak, and implement control measures.

An outbreak investigation, including environmental and infection control assessment, and evaluation of hypotheses using the binomial distribution and case control studies.

A 50-bed medical surgical unit in a hospital in Illinois during the period January 1–July 15, 2006.

Discontinuation of use of opioid delivery via patient-controlled analgesia (PCA) until the source of the outbreak was identified and implementation of new protocols to ensure more rigorous observation of PCA pump cartridge manipulations.

Calculations based on the binomial distribution indicated the probability that all 9 patients with A. xylosoxidans bacteremia were PCA pump users by chance alone was <.001. A subsequent case control study identified PCA pump use for administration of morphine as a risk factor for A. xylosoxidans bacteremia (odds ratio, undefined; P< .001). Having a PCA pump cartridge with morphine started by nurse C was significantly associated with becoming a case-patient (odds ratio, 46; 95% confidence interval, 4.0–525.0; P< .001).

We hypothesize that actions related to diversion of morphine by nurse C were the likely cause of the outbreak. An aggressive pain control program involving the use of opioid medication warrants an equally aggressive policy to prevent diversion of medication by staff.

Infect Control Hosp Epidemiol 2012;33(2):180-184

To detect an outbreak-related source of Legionella, control the outbreak, and prevent additional Legionella infections from occurring.

Epidemiologic investigation of an acute outbreak of hospital-associated Legionnaires disease among outpatients and visitors to a Wisconsin hospital.

Patients with laboratory-confirmed Legionnaires disease who resided in southeastern Wisconsin and had illness onsets during February and March 2010.

Patients with Legionnaires disease were interviewed using a hypothesis-generating questionnaire. On-site investigation included sampling of water and other potential environmental sources for Legionella testing. Case-finding measures included extensive notification of individuals potentially exposed at the hospital and alerts to area healthcare and laboratory personnel.

Laboratory-confirmed Legionnaires disease was diagnosed in 8 patients, all of whom were present at the same hospital during the 10 days prior to their illness onsets. Six patients had known exposure to a water wall-type decorative fountain near the main hospital entrance. Although the decorative fountain underwent routine cleaning and maintenance, high counts of Legionella pneumophila serogroup 1 were isolated from cultures of a foam material found above the fountain trough.

This outbreak of Legionnaires disease was associated with exposure to a decorative fountain located in a hospital public area. Routine cleaning and maintenance of fountains does not eliminate the risk of bacterial contamination. Our findings highlight the need to evaluate the safety of water fountains installed in any area of a healthcare facility.

Infect Control Hosp Epidemiol 2012;33(2):185-191