Contaminated ice machines have been linked to transmission of pathogens in healthcare facilities.

To determine the frequency and sites of contamination of ice machines in multiple healthcare facilities and to investigate potential mechanisms of microorganism dispersal from contaminated ice machines to patients.

Multicenter culture survey and simulation study.

The study took place in 5 hospitals and 2 nursing homes in northeastern Ohio.

We cultured multiple sites on ice machines from patient care areas. To investigate potential mechanisms of microbial dispersal from contaminated ice machines, we observed the use of ice machines and conducted simulations using a fluorescent tracer and cultures.

Samples from 64 ice machines in the 5 hospitals and 2 nursing homes (range, 3–16 per facility) were cultured. Gram-negative bacilli and/or Candida spp were recovered from 100% of drain pans, 52% of ice and/or water chutes, and 72% of drain-pan grilles. During the operation of ice machines, ice often fell through the grille, resulting in splattering, with dispersal of contaminated water from the drain pan to the drain-pan grille, cups, and the hands of those using the ice machine. Contamination of the inner surface of the ice chute resulted in contamination of ice cubes exiting the chute.

Our findings demonstrate that ice machines in healthcare facilities are often contaminated with gram-negative bacilli and Candida species, and provide a potential mechanism by which these organisms may be dispersed. Effective interventions are needed to reduce the risk of dissemination of pathogenic organisms from ice machines.

Infect Control Hosp Epidemiol 2018;39:253–258

We conducted this study to determine what sample volume, concentration, and limit of detection (LOD) are adequate for environmental validation of Legionella control. We also sought to determine whether time required to obtain culture results can be reduced compared to spread-plate culture method. We also assessed whether polymerase chain reaction (PCR) and in-field total heterotrophic aerobic bacteria (THAB) counts are reliable indicators of Legionella in water samples from buildings.

Comparative Legionella screening and diagnostics study for environmental validation of a healthcare building water system.

Veterans Health Administration (VHA) facility water system in central Texas.

We analyzed 50 water samples (26 hot, 24 cold) from 40 sinks and 10 showers using spread-plate cultures (International Standards Organization [ISO] 11731) on samples shipped overnight to the analytical lab. In-field, on-site cultures were obtained using the PVT (Phigenics Validation Test) culture dipslide-format sampler. A PCR assay for genus-level Legionella was performed on every sample.

No practical differences regardless of sample volume filtered were observed. Larger sample volumes yielded more detections of Legionella. No statistically significant differences at the 1 colony-forming unit (CFU)/mL or 10 CFU/mL LOD were observed. Approximately 75% less time was required when cultures were started in the field. The PCR results provided an early warning, which was confirmed by spread-plate cultures. The THAB results did not correlate with Legionella status.

For environmental validation at this facility, we confirmed that (1) 100 mL sample volumes were adequate, (2) 10× concentrations were adequate, (3) 10 CFU/mL LOD was adequate, (4) in-field cultures reliably reduced time to get results by 75%, (5) PCR provided a reliable early warning, and (6) THAB was not predictive of Legionella results.

Infect Control Hosp Epidemiol 2018;39:259–266

Contaminated hands of healthcare workers (HCWs) are an important source of transmission of healthcare-associated infections. Alcohol-based hand sanitizers, while effective, do not provide sustained antimicrobial activity. The objective of this study was to compare the immediate and persistent activity of 2 hand hygiene products (ethanol [61% w/v] plus chlorhexidine gluconate [CHG; 1.0% solution] and ethanol only [70% v/v]) when used in an intensive care unit (ICU).

Prospective, randomized, double-blinded, crossover study

Three ICUs at a large teaching hospital

In total, 51 HCWs involved in direct patient care were enrolled in and completed the study.

All HCWs were randomized 1:1 to either product. Hand prints were obtained immediately after the product was applied and again after spending 4–7 minutes in the ICU common areas prior to entering a patient room or leaving the area. The numbers of aerobic colony-forming units (CFU) were compared for the 2 groups after log transformation. Each participant tested the alternative product after a 3-day washout period.

On bare hands, use of ethanol plus CHG was associated with significantly lower recovery of aerobic CFU, both immediately after use (0.27 ± 0.05 and 0.88 ± 0.08 log10 CFU; P = .035) and after spending time in ICU common areas (1.81 ± 0.07 and 2.17 ± 0.05 log10 CFU; P<.0001). Both the antiseptics were well tolerated by HCWs.

In comparison to the ethanol-only product, the ethanol plus CHG sanitizer was associated with significantly lower aerobic bacterial counts on hands of HCWs, both immediately after use and after spending time in ICU common areas.

Clinicaltrials.gov identifier NCT02258412

Infect Control Hosp Epidemiol 2018;39:267–271

In this study, we sought to establish a comprehensive inventory of infectious risk moments (IRMs), defined as seemingly innocuous yet frequently occurring care manipulations potentially resulting in transfer of pathogens to patients. We also aimed to develop and employ an observational taxonomy to quantify the frequency and nature of IRMs in acute-care settings.

Prospective observational study and establishment of observational taxonomy.

Intensive care unit, general medical ward, and emergency ward of a university-affiliated hospital.

Healthcare workers (HCWs)

Exploratory observations were conducted to identify IRMs, which were coded based on the surfaces involved in the transmission pathway to establish a structured taxonomy. Structured observations were performed using this taxonomy to quantify IRMs in all 3 settings.

Following 129.17 hours of exploratory observations, identified IRMs involved HCW hands, gloves, care devices, mobile objects, and HCW clothing and accessories. A structured taxonomy called INFORM (INFectiOus Risk Moment) was established to classify each IRM according to the source, vector, and endpoint of potential pathogen transfer. We observed 1,138 IRMs during 53.77 hours of structured observations (31.25 active care hours) for an average foundation of 42.8 IRMs per active care hour overall, and average densities of 34.9, 36.8, and 56.3 IRMs in the intensive care, medical, and emergency wards, respectively.

Hands and gloves remain among the most important contributors to the transfer of pathogens within the healthcare setting, but medical devices, mobile objects, invasive devices, and HCW clothing and accessories may also contribute to patient colonization and/or infection. The INFORM observational taxonomy and IRM inventory presented may benefit clinical risk assessment, training and education, and future research.

Infect Control Hosp Epidemiol 2018;39:272–279

To elicit expert consensus on the likelihood of infectious outcomes (patient colonization or infection) following a broad range of infectious risk moments (IRMs) from observations in acute care.

Expert consensus study using modified Delphi technique.

Panel of 40 international experts including nurses, physicians and microbiologists specialized in infectious diseases and infection prevention and control (IPC).

The modified Delphi process consisted of 3 online survey rounds, with feedback of mean ratings and expert comments between rounds. The Delphi survey comprised 52 care scenarios representing observed IRMs organized into 6 sections: hands, gloves, medical devices, mobile objects, invasive procedures, and additional moments. For each scenario, experts indicated the likelihood of both patient colonization and infection on a scale from 0 to 5 (high). Expert ratings were plotted against frequencies of IRMs observed during actual patient care resulting in a risk index.

Following 3 rounds, consensus was achieved for 92 of 104 items (88.5%). The mean ratings across all scenarios for likelihood of colonization and infection were 2.68 and 2.02, respectively. The likelihood of colonization was rated higher than infection for 48 of 52 scenarios. Ratings were significantly higher for colonization (P=.001) and infection (P<.0005) when the scenario involved transfer of pathogens to critical patient sites.

The design of effective IPC strategies requires the selection of behaviors according to their impact on patient outcomes. The IRM index reported here provides a basis for standardizing and prioritizing targets for quality improvement initiatives, training, and future research in acute health care.

Infect Control Hosp Epidemiol 2018;39:280–289

The role of methicillin-resistant Staphylococcus aureus (MRSA) nasal surveillance swabs (nasal swabs) in guiding decisions about prescribing vancomycin is unclear. We aimed to determine the likelihood that patients with negative MRSA nasal swabs develop subsequent MRSA infections; to assess avoidable vancomycin days for patients with negative nasal swabs; and to identify risk factors for having a negative nasal swab and developing a MRSA infection during the intensive care unit (ICU) stay.

This retrospective cohort study was conducted in 6 ICUs at a tertiary-care hospital from December 2013 through June 2015. The negative predictive value (NPV), defined as the ability of a negative nasal swab to predict no subsequent MRSA infection, was calculated. Days of vancomycin continued or restarted after 3 days from the collection time of the first negative nasal swab were determined. A matched case-control study identified risk factors for having a negative nasal swab and developing MRSA infection.

Of 11,441 patients with MRSA-negative nasal swabs, the rate of subsequent MRSA infection was 0.22%. A negative nasal swab had a NPV of 99.4% (95% confidence interval [CI], 99.1%–99.6%). Vancomycin was continued or started after nasal swab results were available in 1,431 patients, translating to 7,364 vancomycin days. No risk factors associated with MRSA infection were identified.

In our hospital with a low prevalence of MRSA transmission, a negative MRSA nasal swab was helpful in identifying patients with low risk of MRSA infection in whom empiric vancomycin therapy could be stopped and in whom the subsequent initiation of vancomycin therapy during an ICU admission could be avoided.

Infect Control Hosp Epidemiol 2018;39:290–296

To analyze whether electronically available comorbid conditions are risk factors for Centers for Disease Control and Prevention (CDC)-defined, hospital-onset Clostridium difficile infection (CDI) after controlling for antibiotic and gastric acid suppression therapy use.

Patients aged ≥18 years admitted to the University of Maryland Medical Center between November 7, 2015, and May 31, 2017.

Comorbid conditions were assessed using the Elixhauser comorbidity index. The Elixhauser comorbidity index and the comorbid condition components were calculated using the International Classification of Disease, Tenth Revision, Clinical Modification (ICD-10-CM) codes extracted from electronic medical records. Bivariate associations between CDI and potential covariates for multivariable regression, including antibiotic use, gastric acid suppression therapy use, as well as comorbid conditions, were estimated using log binomial multivariable regression.

After controlling for antibiotic use, age, proton-pump inhibitor use, and histamine-blocker use, the Elixhauser comorbidity index was a significant risk factor for predicting CDI. There was an increased risk of 1.26 (95% CI, 1.19–1.32) of having CDI for each additional Elixhauser point added to the total Elixhauser score.

An increase in Elixhauser score is associated with CDI. Our study and other studies have shown that comorbid conditions are important risk factors for CDI. Electronically available comorbid conditions and scores like the Elixhauser index should be considered for risk-adjustment of CDC CDI rates.

Infect Control Hosp Epidemiol 2018;39:297–301

To identify the factors associated with first Clostridium difficile infection (CDI) that predict fecal microbiota transplantation (FMT) for recurrent CDI

We carried out a retrospective single-center cohort study to compare the clinical characteristics of 200 patients who underwent FMT for recurrent CDI to 75 patients who did not.

A single academic hospital in the United States

Adult patients

The time from first to second CDI correlated to subsequent FMT use. Concomitant inflammatory bowel disease (IBD; P=.002), use of immunosuppressive therapy (P=.04), and use of metronidazole within 2 months before the first CDI (P=.02) correlated positively to subsequent FMT in univariate analysis. The use of oral vancomycin for first CDI was more common in those who required FMT than those who did not in univariate (P=.02) and multivariate (P=.03) analyses. In contrast, intravenous vancomycin use within 2 months before the first CDI reduced the risk for FMT in univariate P=.000003) and multivariate (P=.0001) analyses. Black patients with recurrent CDI were less likely to receive FMT than white patients (P=.00005). Patients who received FMT were also less likely to have comorbidities.

This study provides important insights into the factors predictive for FMT in patients with recurrent CDI and highlights the potential racial and medical characteristics that affect the access of the patients to FMT.

Infect Control Hosp Epidemiol 2018;39:302–306

To reduce inappropriate antimicrobial prescribing across ambulatory care, understanding the patient-, provider-, and practice-level characteristics associated with antibiotic prescribing is essential. In this study, we aimed to elucidate factors associated with inappropriate antimicrobial prescribing across urgent care, family medicine, and pediatric and internal medicine ambulatory practices.

Data for this retrospective cohort study were collected from outpatient visits for common upper respiratory conditions that should not require antibiotics. The cohort included 448,990 visits between January 2014 and May 2016. Carolinas HealthCare System urgent care, family medicine, internal medicine and pediatric practices were included across 898 providers and 246 practices.

Prescribing rates were reported per 1,000 visits. Indications were defined using the International Classification of Disease, Ninth and Tenth Revisions, Clinical Modification (ICD-9/10-CM) criteria. In multivariable models, the risk of receiving an antibiotic prescription was reported with adjustment for practice, provider, and patient characteristics.

The overall prescribing rate in the study cohort was 407 per 1,000 visits (95% confidence interval [CI], 405–408). After adjustment, adult patients seen by an advanced practice practitioner were 15% more likely to receive an antimicrobial than those seen by a physician provider (incident risk ratio [IRR], 1.15; 95% CI, 1.03–1.29). In the pediatric sample, older providers were 4 times more likely to prescribe an antimicrobial than providers aged ≤30 years (IRR, 4.21; 95% CI, 2.96–5.97).

Our results suggest that patient, practice, and provider characteristics are associated with inappropriate antimicrobial prescribing. Future research should target antibiotic stewardship programs to specific patient and provider populations to reduce inappropriate prescribing compared to a “one size fits all” approach.

Infect Control Hosp Epidemiol 2018;39:307–315

To assess antimicrobial prescriber knowledge, attitudes, and practices (KAP) regarding antimicrobial stewardship (AS) and associated barriers to optimal prescribing.

Cross-sectional survey.

Online survey.

A convenience sample of 2,900 US antimicrobial prescribers at 5 acute-care hospitals within a hospital network.

The following characteristics were assessed with an anonymous, online survey in February 2015: attitudes and practices related to antimicrobial resistance, AS programs, and institutional AS resources; antimicrobial prescribing and AS knowledge; and practices and confidence related to antimicrobial prescribing.

In total, 402 respondents completed the survey. Knowledge gaps were identified through case-based questions. Some respondents sometimes selected overly broad therapy for the susceptibilities given (29%) and some “usually” or “always” preferred using the most broad-spectrum empiric antimicrobials possible (32%). Nearly all (99%) reported reviewing antimicrobial appropriateness at 48–72 hours, but only 55% reported “always” doing so. Furthermore, 45% of respondents felt that they had not received adequate training regarding antimicrobial prescribing. Some respondents lacked confidence selecting empiric therapy using antibiograms (30%), interpreting susceptibility results (24%), de-escalating therapy (18%), and determining duration of therapy (31%). Postprescription review and feedback (PPRF) was the most commonly cited AS intervention (79%) with potential to improve patient care.

Barriers to appropriate antimicrobial selection and de-escalation of antimicrobial therapy were identified among front-line prescribers in acute-care hospitals. Prescribers desired more AS-related education and identified PPRF as the most helpful AS intervention to improve patient care. Educational interventions should be preceded by and tailored to local assessment of educational needs.

Infect Control Hosp Epidemiol 2018;39:316–322