To examine tweeting activity, networks, and common topics mentioned on Twitter at 4 international infection control and infectious disease conferences.

A cross-sectional study.

An independent company was commissioned to undertake a Twitter ‘trawl’ each month between July 1, 2016, and November 31, 2016. The trawl identified any tweets that contained the official hashtags of the conferences for (1) the UK Infection Prevention Society, (2) IDWeek 2016, (3) the Federation of Infectious Society/Hospital Infection Society, and (4) the Australasian College for Infection Prevention and Control. Topics from each tweet were identified, and an examination of the frequency and timing of tweets was performed. A social network analysis was performed to illustrate connections between users. A multivariate binary logistic regression model was developed to explore the predictors of ‘retweets.’

In total, 23,718 tweets were identified as using 1 of the 2 hashtags of interest. The results demonstrated that the most tweets were posted during the conferences. Network analysis demonstrated a diversity of twitter networks. A link to a web address was a significant predictor of whether a tweet would be retweeted (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.9–2.1). Other significant factors predicting a retweet included tweeting on topics such as Clostridium difficile (OR, 2.0; 95% CI, 1.7–2.4) and the media (OR, 1.8; 95% CI, 1.6–2.0). Tweets that contained a picture were significantly less likely to be retweeted (OR, 0.06; 95% CI, 0.05–0.08).

Twitter is a useful tool for information sharing and networking at infection control conferences.

Infect Control Hosp Epidemiol 2017;38:1271–1276

To investigate whether the safety culture of a hospital unit is associated with the ability to improve.

Qualitative investigation of safety culture on hospital units following a before-and-after trial on hand hygiene.

VU University Medical Center, a tertiary-care hospital in the Netherlands.

With support from hospital management, we implemented a hospital-wide program to improve compliance. Over 2 years, compliance was measured through direct observation, twice before, and 4 times after interventions. We analyzed changes in compliance from baseline, and selected units to evaluate safety culture using a positive deviance approach: the hospital unit with the highest hand hygiene compliance and 2 units that showed significant improvement (21% and 16%, respectively) were selected as high performing. Another 2 units showed no improvement and were selected as low performing. A blinded, independent observer conducted interviews with unit management, physicians, and nurses, based on the Hospital Survey on Patient Safety Culture. Safety culture was categorized as pathological (lowest level), reactive, bureaucratic, proactive, or generative (highest level).

Overall, 3 units showed a proactive or generative safety culture and 2 units had bureaucratic or pathological safety cultures. When comparing compliance and interview results, high-performing units showed high levels of safety culture, while low-performing units showed low levels of safety culture.

Safety culture is associated with the ability to improve hand hygiene. Interventions may not be effective when applied in units with low levels of safety culture. Although additional research is needed to corroborate our findings, the safety culture on a unit can benefit from enhancement strategies such as team-building exercises. Strengthening the safety culture before implementing interventions could aid improvement and prevent nonproductive interventions.

Infect Control Hosp Epidemiol 2017;38:1277–1283

Biofilm has been implicated in bacterial persistence and survival after endoscope reprocessing. In this study, we assessed the impact of different methods of reprocessing on organic residues and viable bacteria after repeated rounds of biofilm formation when each was followed by full reprocessing.

ATS-2015, an artificial test soil containing 5–8 Log10 colony-forming units (CFU) of Enterococcus faecalis and Pseudomonas aeruginosa, was used to form biofilm in polytetrafluroethylene channels overnight on 5 successive days. Each successive day, full pump-assisted cleaning using bristle brushes or pull-through devices in combination with enzymatic or nonenzymatic detergents followed by fully automated endoscope reprocessor disinfection using peracetic acid was performed. Residuals were visualized by scanning electron microscopy (SEM). Destructive testing was used to assess expected cutoffs for adenosine triphosphate (ATP; <200 relative light units), protein (<2 µg/cm2), and viable bacteria count (0 CFU).

Protein residuals were above 2 µg/cm2, but ATP residuals were <200 relative light units for all methods tested. Only when enzymatic cleaner was used for cleaning were there no viable bacteria detected after disinfection irrespective of whether bristle brushes or pull-through devices were used. SEM revealed that some residual debris remained after all reprocessing methods, but more residuals were detected when a nonenzymatic detergent was used.

Surviving E. faecalis and P. aeruginosa were only detected when the non-enzymatic detergent was used, emphasizing the importance of the detergent used for endoscope channel reprocessing. Preventing biofilm formation is critical because not all current reprocessing methods can reliably eliminate viable bacteria within the biofilm matrix.

Infect Control Hosp Epidemiol 2017;38:1284–1290

To evaluate host characteristics, mode of infection acquisition, and infection control procedures in patients with a positive respiratory syncytial virus (RSV) test result after the introduction of the GenXpert Influenza/RSV polymerase chain reaction (PCR) assay.

Retrospective cohort study.

Adults with a positive PCR test result for RSV who were hospitalized in a tertiary academic medical center between January 2015 and December 2016 were included in this study. Our infection control policy applies contact isolation precautions only for immunocompromised patients.

Patients were identified through 2 databases, 1 consisting of patients isolated because of RSV infection and 1 with automatically collected laboratory results. Baseline and clinical characteristics were collected through a retrospective medical chart review. The rate of and clinical factors associated with healthcare-associated RSV infections were evaluated.

In total, 108 episodes in 106 patients hospitalized with a positive Xpert RSV test result were recorded during the study period. Among them, 11 episodes were healthcare-associated infections (HAIs) and 97 were community-acquired infections (CAIs). The mean length of hospital stay (LOS, 40.2 vs 11.2 days), the mean number of room switches (3.5 vs 1.7) and ward switches (1.5 vs 0.4), and the mean numbers of contact patients (9.9 vs 3.8) were significantly longer and higher in the HAI group than in the CAI group (P<.0001). Surveillance of microbiology records and clinical data did not reveal evidence for a cluster or an epidemic during the 2-year observation period.

The introduction of a rapid molecular diagnostic test systematically applied to patients with influenza-like illness may challenge current infection control policies. In our study, patients with HAIs had a prolonged hospital stay and a high number of contact patients, and they switched rooms and wards frequently.

Infect Control Hosp Epidemiol 2017;38:1291–1297

Surveillance is an important strategy to reduce the incidence of surgical site infections (SSIs). We investigated whether prior, multiple-, or repetitive surgeries are risk factors for SSI and whether they should be preserved in the protocol of the Dutch national SSI surveillance network.

Dutch national SSI surveillance data 2012–2015 were selected, including 34 commonly performed procedures from 8 major surgical specialties. Definitions of SSIs followed international standardized criteria. We used multivariable multilevel logistic regression techniques to evaluate whether prior, multiple-, or repetitive procedure(s) are risk factors for SSIs. We considered surgeries clustered within partnerships of medical specialists and within hospitals (random effects) and different baseline risks between surgical specialties (fixed effects). Several patient and surgical characteristics were considered possible confounders and were included where necessary. We performed analyses for superficial and deep SSIs combined as well as separately.

In total, 115,943 surgeries were reported by 85 hospitals; among them, 2,960 (2.6%) resulted in SSIs (49.3% deep SSIs). The odds ratio (OR) for having prior surgery was 0.94 (95% confidence interval [CI], 0.74–1.20); the OR for repetitive surgery was 2.39 (95% CI, 2.06–2.77); and the OR for multiple surgeries was1.27 (95% CI, 1.07–1.51). The latter effect was mainly caused by prolonged duration of surgery.

Multiple- and repetitive surgeries significantly increased the risk of an SSI, whereas prior surgery did not. Therefore, prior surgery is not an essential data item to include in the national SSI surveillance network. The increased risk of SSIs for multiple surgeries was mainly caused by prolonged duration of surgery, therefore, it may be sufficient to report only duration of surgery to the surveillance network, instead of both (the variables duration of surgery and multiple surgeries).

Infect Control Hosp Epidemiol 2017;38:1298–1305

We describe the use of implementation science at the unit level and organizational level to guide an intervention to reduce central-line–associated bloodstream infections (CLABSIs) in a high-volume, regional, burn intensive care unit (BICU).

A single center observational quasi-experimental study.

A regional BICU in Maryland serving 300–400 burn patients annually.

In 2011, an organizational-level and unit-level intervention was implemented to reduce the rates of CLABSI in a high-risk patient population in the BICU. At the organization level, leaders declared a goal of zero infections, created an infrastructure to support improvement efforts by creating a coordinating team, and engaged bedside staff. Performance data were transparently shared. At the unit level, the Comprehensive Unit-based Safety Program (CUSP)/ Translating Research Into Practice (TRIP) model was used. A series of interventions were implemented: development of new blood culture procurement criteria, implementation of chlorhexidine bathing and chlorhexidine dressings, use of alcohol impregnated caps, routine performance of root-cause analysis with executive engagement, and routine central venous catheter changes.

The use of an implementation science framework to guide multiple interventions resulted in the reduction of CLABSI rates from 15.5 per 1,000 central-line days to zero with a sustained rate of zero CLABSIs over 3 years (rate difference, 15.5; 95% confidence interval, 8.54–22.48).

CLABSIs in high-risk units may be preventable with the a use a structured organizational and unit-level paradigm.

Infect Control Hosp Epidemiol 2017;38:1306–1311

To characterize the microbial disruption indices of hospitalized patients to predict colonization with multidrug-resistant organisms (MDROs).

A cross-sectional survey of the fecal microbiome was conducted in a tertiary referral, acute-care hospital in Boston, Massachusetts.

The study population consisted of adult patients hospitalized in general medical/surgical wards.

Rectal swabs were obtained from patients within 48 hours of hospital admission and screened for MDRO colonization using conventional culture techniques. The V4 region of the 16S rRNA gene was sequenced to assess the fecal microbiome. Microbial diversity and composition, as well as the functional potential of the microbial communities present in fecal samples, were compared between patients with and without MDRO colonization.

A total of 44 patients were included in the study, of whom 11 (25%) were colonized with at least 1 MDRO. Reduced microbial diversity and high abundance of metabolic pathways associated with multidrug-resistance mechanisms characterized the fecal microbiome of patients colonized with MDRO at hospital admission.

Our data suggest that microbial disruption indices may be key to predicting MDRO colonization and could provide novel infection control approaches.

Infect Control Hosp Epidemiol 2017;38:1312–1318

Mortality associated with infections caused by carbapenem-resistant Enterobacteriaceae (CRE) is higher than mortality due to carbapenem-sensitive pathogens.

To examine the association between mortality from bacteremia caused by carbapenem-resistant (CRKP) and carbapenem-sensitive Klebsiella pneumoniae (CSKP) and to assess the impact of appropriate initial antibiotic therapy (IAT) on mortality.

Systematic review and meta-analysis

We searched MEDLINE, EMBASE, CINAHL, and Wiley Cochrane databases through August 31, 2016, for observational studies reporting mortality among adult patients with CRKP and CSKP bacteremia. Search terms were related to Klebsiella, carbapenem-resistance, and infection. Studies including fewer than 10 patients per group were excluded. A random-effects model and meta-regression were used to assess the relationship between carbapenem-resistance, appropriateness of IAT, and mortality.

Mortality was higher in patients who had CRKP bacteremia than in patients with CSKP bacteremia (15 studies; 1,019 CRKP and 1,148 CSKP patients; unadjusted odds ratio [OR], 2.2; 95% confidence interval [CI], 1.8–2.6; I2=0). Mortality was lower in patients with appropriate IAT than in those without appropriate IAT (7 studies; 658 patients; unadjusted OR, 0.5; 95% CI, 0.3–0.8; I2=36%). CRKP patients (11 studies; 1,326 patients; 8-year period) were consistently less likely to receive appropriate IAT (unadjusted OR, 0.5; 95% CI, 0.3–0.7; I2=43%). Our meta-regression analysis identified a significant association between the difference in appropriate IAT and mortality (OR per 10% difference in IAT, 1.3; 95% CI, 1.0–1.6).

Appropriateness of IAT is an important contributor to the observed difference in mortality between patients with CRKP bacteremia and patients with CSKP bacteremia.

Infect Control Hosp Epidemiol 2017;38:1319–1328

We sought to evaluate the role healthcare providers play in carbapenem-resistant Enterobacteriaceae (CRE) acquisition among hospitalized patients.

A 1:4 case-control study with incidence density sampling.

Academic healthcare center with regular CRE perirectal screening in high-risk units.

We included case patients with ≥1 negative CRE test followed by positive culture with a length of stay (LOS) >9 days. For controls, we included patients with ≥2 negative CRE tests and assignment to the same unit set as case patients with a LOS >9 days.

Controls were time-matched to each case patient. Case exposure was evaluated between days 2 and 9 before positive culture and control evaluation was based on maximizing overlap with the case window. Exposure sources were all CRE-colonized or -infected patients. Nonphysician providers were compared between study patients and sources during their evaluation windows. Dichotomous and continuous exposures were developed from the number of source-shared providers and were used in univariate and multivariate regression.

In total, 121 cases and 484 controls were included. Multivariate analysis showed odds of dichotomous exposure (≥1 source-shared provider) of 2.27 (95% confidence interval [CI], 1.25–4.15; P=.006) for case patients compared to controls. Multivariate continuous exposure showed odds of 1.02 (95% CI, 1.01–1.03; P=.009) for case patients compared to controls.

Patients who acquire CRE during hospitalization are more likely to receive care from a provider caring for a patient with CRE than those patients who do not acquire CRE. These data support the importance of hand hygiene and cohorting measures for CRE patients to reduce transmission risk.

Infect Control Hosp Epidemiol 2017;38:1329–1334

To determine the scope, source, and mode of transmission of a multifacility outbreak of extensively drug-resistant (XDR) Acinetobacter baumannii.

Outbreak investigation.

Residents and patients in skilled nursing facilities, long-term acute-care hospital, and acute-care hospitals.

A case was defined as the incident isolate from clinical or surveillance cultures of XDR Acinetobacter baumannii resistant to imipenem or meropenem and nonsusceptible to all but 1 or 2 antibiotic classes in a patient in an Oregon healthcare facility during January 2012–December 2014. We queried clinical laboratories, reviewed medical records, oversaw patient and environmental surveillance surveys at 2 facilities, and recommended interventions. Pulsed-field gel electrophoresis (PFGE) and molecular analysis were performed.

We identified 21 cases, highly related by PFGE or healthcare facility exposure. Overall, 17 patients (81%) were admitted to either long-term acute-care hospital A (n=8), or skilled nursing facility A (n=8), or both (n=1) prior to XDR A. baumannii isolation. Interfacility communication of patient or resident XDR status was not performed during transfer between facilities. The rare plasmid-encoded carbapenemase gene blaOXA-237 was present in 16 outbreak isolates. Contact precautions, chlorhexidine baths, enhanced environmental cleaning, and interfacility communication were implemented for cases to halt transmission.

Interfacility transmission of XDR A. baumannii carrying the rare blaOXA-237 was facilitated by transfer of affected patients without communication to receiving facilities.

Infect Control Hosp Epidemiol 2017;38:1335–1341

To compare incidence densities of methicillin-resistant Staphylococcus aureus (MRSA) or extended-spectrum β-lactamase–producing Enterobacteriaceae (ESBLE) acquisition in the intensive care unit (ICU) before and after discontinuation of contact precautions (CP) and application of standard precautions (SP).

Prospective noninferiority before-and-after study comparing 2 periods: January 1, 2012, to January 31, 2014 (the CP period) and February 1, 2014, to February 29, 2016 (the SP period).

A 16-bed polyvalent ICU in France with only single-bed rooms with dedicated equipment and reusable medical devices.

All patients admitted to the ICU during the CP and SP periods were included: 1,547 and 1,577 patients, respectively.

Incidence densities of ICU-acquired MRSA or ESBLE were determined per 1,000 patient days. Other studied factors included (1) patient characteristics, (2) incidence densities of MRSA or ESBLE carried at admission, (3) compliance with hand hygiene protocols, and (4) antibiotic consumption.

Incidence densities of ICU-acquired MRSA were 0.82 (95% confidence interval [CI], 0.31–1.33) and 0.79 (95% CI, 0.30–1.29) per 1,000 patient days during the CP and SP periods, respectively. For ESBLE, values were 2.7 (95% CI, 1.78–3.62) and 2.06 (95% CI, 1.27–2.86) per 1,000 patient days. These rates were significantly nonsuperior during the SP period compared to CP period, with a margin of 1 per 1,000 patient days for both MRSA (P=.002) and ESBLE (P=.004). Other factors were comparable during the 2 periods. Only ESBLE carried at admission was inferior during the SP period. We observed a high level of compliance to hand hygiene protocols.

Discontinuing CP did not increase acquired MRSA and ESBLE in our ICU with single rooms with dedicated equipment, strict application of hand hygiene, medical and paramedical leadership, and good antibiotic stewardship.

Infect Control Hosp Epidemiol 2017;38:1342–1350

To determine the impact of recurrent Clostridium difficile infection (RCDI) on patient behaviors following illness.

Using a computer algorithm, we searched the electronic medical records of 7 Chicago-area hospitals to identify patients with RCDI (2 episodes of CDI within 15 to 56 days of each other). RCDI was validated by medical record review. Patients were asked to complete a telephone survey. The survey included questions regarding general health, social isolation, symptom severity, emotional distress, and prevention behaviors.

In total, 119 patients completed the survey (32%). On average, respondents were 57.4 years old (standard deviation, 16.8); 57% were white, and ~50% reported hospitalization for CDI. At the time of their most recent illness, patients rated their diarrhea as high severity (58.5%) and their exhaustion as extreme (30.7%). Respondents indicated that they were very worried about getting sick again (41.5%) and about infecting others (31%). Almost 50% said that they have washed their hands more frequently (47%) and have increased their use of soap and water (45%) since their illness. Some of these patients (22%–32%) reported eating out less, avoiding certain medications and public areas, and increasing probiotic use. Most behavioral changes were unrelated to disease severity.

Having had RCDI appears to increase prevention-related behaviors in some patients. While some behaviors are appropriate (eg, handwashing), others are not supported by evidence of decreased risk and may negatively impact patient quality of life. Providers should discuss appropriate prevention behaviors with their patients and should clarify that other behaviors (eg, eating out less) will not affect their risk of future illness.

Infect Control Hosp Epidemiol. 2017;38:1351–1357