Background: Unlike Staphylococcus aureus bacteremia, the impact of ID consultation for gram negative bacteremia (GNB) has not been well studied. Recent literature has supported shorter courses of antibiotics in adults with uncomplicated GNB. We examined duration of therapy for adult patients with uncomplicated GNB over a period of time during which ID consultation for GNB was made mandatory. Method: NorthShore University HealthSystem is a 4 hospital, 828 bed hospital system located in the northern suburbs of Chicago. Data were collected retrospectively from 1/1/2018 through 12/31/2021 for patients 18 years or older hospitalized with an uncomplicated bloodstream infection due to Escherichia coli, Klebsiella species or Proteus species. This study was approved by the Institutional Review Board. All sources of infection were included. Days of effective antibiotic therapy were extracted manually by two pharmacists and an infectious diseases physician. During the study period, two major changes occurred: 1) the Physician Practice Council of NorthShore University Healthsystem voted in favor of a mandatory ID consultation for GNB and 2) the ID division developed a treatment algorithm for GNB management with an emphasis on shorter antibiotic duration in uncomplicated cases. This study was divided into three time periods: Pre-ID consultation – 1/1/2018 – 8/31/2019; Transition – 9/1/2019 – 5/31/2020 (after mandatory ID consultation, before ID division consensus achieved); Post-ID Consensus – 6/1/2020 – 12/31/21. Primary outcome was duration of antibiotic therapy. Secondary outcomes included in-hospital all-cause mortality and 30 day readmission. Continuous variables were described using median and interquartile range, and categorical data using frequency and prevalence. Kruskal-Wallis rank sum test for continuous and χ2 for categorical variables was used to verify similarity among the pre-ID consultation, transition and post-ID consensus periods. The analysis was performed using Python. Result: 1026 patients were included in the study. Pathogens included 773 E. coli (75.4%), 193 Klebsiella species (18.8%) and 60 Proteus species (5.9%). Length of stay, 30 day readmission and in-hospital mortality were not statistically significantly different when comparing pre-ID consultation and post-ID consensus time periods. Total duration of therapy was statistically significantly shorter in the post-ID consensus period (p < 0.001). Conclusion: Mandatory ID consultation and development of an ID consensus approach can shorten antibiotic duration in uncomplicated GNB. Further analysis will explore timing of transition to oral therapy and syndromic differences.

Background: Pediatric urinary tract infections represent the most common pediatric infection with increasing gram-negative antibiotic resistance. Overutilization of antimicrobials including third generation cephalosporins are known drivers of this resistance. Antimicrobial stewardship (AS) efforts have recently shown that antibiotic selection may be influenced by patient race. Implementation science (IS) can provide frameworks and strategies to improve antimicrobial utilization and equity. Methods: This was a pre/post study of 2 geographically different children’s hospitals general pediatric floors assessing the impact of a set of implementation strategies developed to improve provider knowledge of best practice antimicrobials (based on local susceptibilities for treatment of UTI’s) and influence uptake of best practice prescribing. IS strategies included provider education, local clinical champion and opinion leader involvement, leadership involvement, local policy changes, and stakeholder co-design of decision support tools (a clinical pathway, a specific ITI antibiogram, and a dynamic order set). No education was provided regarding racial differences in prescribing habits. Outcomes were measured utilizing a portion of the RE-AIM Framework of assessing adoption of “Right” antibiotic, order set adoption, and equitable reach (racial differences in prescribing). Results: Hospital A and B had a first-generation cephalosporin prescription rate of 29.7% (n=441) and 20.6% (n-557) pre implementation and 44.6% (n=84) and 47.5% (n=118) post (p < 0 .001). Both hospitals also saw a significant reduction in third-generation cephalosporins. In Hospital A, APRN’s were more likely to prescribe a first generation cephalosporin (52.4%) than a DO (42.1%) or MD (26.4%) pre-implementation (p=0.004). In Hospital B, APRN’s were less likely to prescribe first generation cephalosporins (5.4%) than a DO (28.9%) or MD (19.4%) pre-implementation (p=0.004). No statistical significance was seen post implementation for antimicrobial selection by provider type for either hospital. Based on race, both hospitals had Black and Other patients receiving more first-generation cephalosporins while white patients were more likely to receive third-generation cephalosporins (p=0.033) pre implementation. No statistical significance was seen post implementation for antimicrobial selection based on race. No improvement was seen in order set utilization. Conclusion: With order set utilization not improving with implementation of new dynamic order set, other strategies such as education, clinical champion and opinion leader involvement, and provision of a local UTI antibiogram were likely contributors to the improvement in best antimicrobial for treatment of UTI’s. Further mixed method research is warranted to improve understanding of the relative performance of our strategies, especially the lack of provider adoption of the novel dynamic order set.

Disclosure: Jessica Snowden: Advisory board - Pfizer

Background: The molecular and epidemiological landscape of C. difficile infection (CDI) has evolved markedly in the last decade; however, limited information is available contrasting differences between adult and pediatric populations. We describe a multicenter study evaluating healthcare-associated (HA) and community-associated (CA) adult and pediatric-CDI identified in the Canadian Nosocomial Infection Surveillance Program (CNISP) network from 2015 to 2022. Methods: Hospitalized patients with CDI were identified from up to 84 hospitals between 2015–2022 using standardized case definitions. Cases were confirmed by PCR, cultured, and further characterized using ribotyping and E-test. We used two-tailed tests for significance (p≤0.05). Results: Of 30,817 cases reported, 29,245 were adult cases [HA-CDI (73.2%), CA-CDI (26.8%)] and 1,572 were pediatric cases [HA-CDI (77.7%), CA-CDI (22.3%)]. From 2015 to 2022, HA-CDI rates decreased 19.7% (p=0.007) and 29.4% (p=0.004) in adult and pediatric populations, respectively (Figure 1). CA-CDI rates remained relatively stable in the adult population (p=0.797), while decreasing 60.7% in the pediatric population (p=0.013). Median ages of adult and pediatric patients were 70 (interquartile range (IQR), 58–80) and seven (IQR, 3–13) years, respectively. Thirty-day all-cause mortality was significantly higher among adult vs. Pediatric CDI patients (11.0% vs 1.4%, p < 0.0001). No significant differences in other severe outcomes were found. Ribotyping and susceptibility data were available for 4,620 samples: 3,558 adult (77.0%) and 1,062 pediatric (23.0%). The predominant adult and pediatric ribotypes (RT) were 106 (12.2/16.2%), 027 (11.4/3.2%), and 014 (8.8/8.2%). Overall, RT027 prevalence significantly decreased from 17.9% in 2015 to 3.2% in 2022 (p=0.003), while RT106 increased from 8.5% to 14.4%. Resistance rates among adult and pediatric isolates were similar for all antimicrobials tested except moxifloxacin (16.2% vs. 6.2%, p < 0.0001, respectively). Adult moxifloxacin resistance decreased from 30% to 6.3% from 2015 to 2022 (p=0.006). Adults with moxifloxacin-resistant CDI were older (median: 74 vs. 69 years, p < 0.001) and had higher thirty-day all-cause mortality (13% vs. 9.8%, p=0.041) and recurrence (10% vs. 5.7%, p < 0.001) compared to those with moxifloxacin non-resistant CDI, while these trends were not observed in pediatric patients. Among RT027 strains, moxifloxacin resistance decreased from 91.0% in 2015 to 7.1% in 2022. There was one metronidazole-resistant pediatric sample in 2018 and no resistance to vancomycin or tigecycline in either population. Conclusion: We have found differences in the epidemiological and molecular characteristics of adult and pediatric CDI, with higher thirty-day all-cause mortality among adults. Overall, RT106 has replaced RT027 as the predominant ribotype with a concomitant decrease in fluoroquinolone resistance.

Background: During the COVID-19 pandemic, rates of central line bloodstream infections (CLABSI) increased nationally. Studies pre-pandemic showed improved CLABSI rates with implementation of a standardized vascular access team (VAT).[PL1] [PL2] [mi3] Varying VAT resources and coverage existed in our 10 acute care facilities (ACF) prior to and during the pandemic. VAT scope also varied in 1) process for line selection during initial placement, 2) ability to place a peripherally inserted central catheter (PICC), midline or ultrasound-guided peripheral IV in patients with difficult vascular access, 3) ownership of daily assessment of central line (CL) necessity, and 4) routine CL dressing changes. We aimed to define and implement the ideal VAT structure and evaluate the impact on CLABSI standardized infection ratios (SIR) and rates prior to and during the pandemic. Methods: A multidisciplinary workgroup including representatives from nursing, infection prevention, and vascular access was formed to understand the current state of VAT responsibilities across all ACFs. The group identified key responsibilities a VAT should conduct to aid in CLABSI prevention. Complete VAT coverage[mi4] was defined as the ability to conduct the identified responsibilities daily. We compared the SIR and CLABSI rates between hospitals who had complete VAT (CVAT) coverage to hospitals with incomplete VAT (IVAT) coverage. Given this work occurred during the pandemic, we further stratified our analysis based on a time frame prior to the pandemic (1/2015 – 12/2019) and intra-pandemic (1/2020 - 12/2022). Results: The multidisciplinary team identified 6 key components of complete VAT coverage: Assessment for appropriate line selection prior to insertion, ability to insert PICC and midlines, daily CL and midline care and maintenance assessments, daily assessment of necessity for CL, and weekly dressing changes for CL and midlines[NA5] . A cross walk of VAT scope (Figure 1) was performed in October 2022 which revealed two facilities (A and E) which met CVAT criteria. Pre-pandemic, while IVAT CLABSI rates and SIR were higher than in CVAT units, the difference was not statistically significant. During the pandemic, however, CLABSI rates and SIR were 40-50% higher in IVAT compared to CVAT facilities (Incident Rate Ratio 1.5, 95% CI 1.1-2.0 and SIR Relative Ratio 1.4, 95% CI1.1-1.9 respectively) (Table 1). Conclusions: CLABSI rates were lower in facilities with complete VAT coverage prior to and during the COVID-19 pandemic suggesting a highly functioning VAT can aid in preventing CLABSIs, especially when a healthcare system is stressed and resources are limited.

Cultures from urinary catheters are often ordered without indication, leading to possible misdiagnosis of catheter-associated urinary tract infections (CAUTI), increasing antimicrobial use, and C difficile. We implemented a diagnostic stewardship intervention for urine cultures from catheters in a community hospital that led to a reduction in cultures and CAUTIs.

Background: The COVID-19 pandemic has placed an enormous strain on the healthcare system, including infection prevention and control. The response to the COVID-19 pandemic required extraordinary resources, which were often diverted from routine infection prevention and control activities and may have contributed to increased rates of HAI in the acute care setting. However, the impact of the COVID-19 pandemic on infection prevention and control departments, including staffing and resources, and on routine infection prevention and control activities is not well-described. The objective of this study was to describe the impact of the COVID-19 pandemic on IPC departments and department response to the pandemic. Methods: Between August and December of 2023, we conducted an electronic survey of all acute care facilities participating in the National Healthcare Safety Network. Survey data were analyzed using descriptive statistics. Results: Over 594 infection control departments participated in the survey, representing 1,400 NHSN facilities (20% response rate based on number of eligible NHSN facilities). Half of the respondents reported that their hospital experienced increases in the following HAI rates during the first two years of the pandemic: central-line associated bloodstream infections (54%), catheter-associated urinary tract infections (46%) and ventilator associated pneumonia (45%). When asked to identify the top three contributors to increased HAI rates in their facility, respondents cited the following factors: staffing shortages (70%), patient acuity (69%), use of travel nurses (48%), increased device utilization (37%), and reduced bedside acuity (31%). Respondents reported that their department utilized the following actions to decrease these HAI rates: increased rounding and monitoring of IPC procedures (81%), reeducation of frontline staff on IPC policies and procedures (77%), environmental care rounds (69%), monitoring of isolation compliance (66%), HAI Task Force/Committee (57%), nurse-driven catheter removal protocols (53%), and insertion prevention protocols (53%). When asked if the department experienced applied pressure or attempts to influence HAI reporting due to the increase in HAI rates in the facility experienced in the wake of the pandemic, 19% of respondents reported increased pressure from management/C-suite and 7% reported increased pressure from providers. Conclusion: The COVID-19 pandemic had a substantial impact on IPC departments in acute care hospitals and had a profound effect on IPC staffing, resources and routine IPC activities. Future work needs to identify best practices and lessons learned from the pandemic to inform future pandemic preparedness.

Background: Multidrug-resistant Gram-negative bacteria are a major cause of sepsis among hospitalized neonates globally. Aqueous chlorhexidine gluconate (CHG) skin antisepsis has been shown to be safe for use in infants; however, its sustained effectiveness in preventing Gram-negative pathogen colonization, bloodstream infection (BSI), and mortality is unclear. Methods: We conducted a period prevalence survey, with 26 sampling events over 12 months (18 October 2022 – 31 October 2023) at a 33-bed neonatal unit in a tertiary public hospital in Botswana where ESBL-producing Klebsiella pneumoniae and carbapenem-resistant Acinetobacter baumannii are leading causes of BSI. Perirectal and periumbilical skin swabs were collected every two weeks from all inpatients. Swabs were inoculated onto chromogenic media selective and differential for extended-spectrum beta-lactamase producing Enterobacterales (ESBL-E) and Acinetobacter spp. (CHROMagar™ ESBL, Acinetobacter). Colonization status was determined based on culture growth and colony morphology. Contemporaneous data on all-cause mortality and BSI were abstracted from routine surveillance records. Pre- and post-CHG prevalences were compared using a simple Chi-square test. During the surveillance period, an outbreak of K. pneumoniae linked to contaminated multi-use vials was detected, thus BSIs and deaths during the outbreak period (2 February–6 April, 2023) were excluded. In February 2023, the hospital infection prevention and control (IPC) team introduced twice-weekly whole-body cleansing with commercially available 2% aqueous CHG, performed by caregivers and healthcare workers on neonates >24 hours old and weighing ≥1 kg until discharge. Results: There were significant decreases in ESBL-E and Acinetobacter skin and perirectal colonization following the CHG intervention (Table 1; Figure 1). After the CHG intervention, the incidence of Acinetobacter BSIs declined significantly and there was a trend toward a decline in other BSIs and mortality. No adverse events associated with CHG were reported. Conclusions: Twice-weekly CHG application was temporally associated with significant reductions in neonatal ESBL-E and Actinetobacter skin and perirectal colonization and Acinetobacter BSI. This analysis was limited by a short pre-intervention surveillance period and thus may have been influenced by confounders such as seasonality, and intensified IPC efforts following the outbreak. Analysis of the routine CHG use in other settings and over longer surveillance periods are needed to better understand its effectiveness as an IPC strategy in settings where neonatal sepsis incidence is high. Table 1. Colonization prevalence, BSI incidence, and mortality surrounding introduction of CHG skin cleansing in a neonatal unit, 18 October 2022 – 31 October 2023.

Background: Candida auris, a multi-drug resistant fungal pathogen, was introduced to Tennessee in 2021. There are limited studies on the spread of C. auris in highly specialized care settings including outpatient dialysis facilities. Facilities are concerned that C. auris transmission is difficult to prevent in this setting due to patient vulnerability, treatment frequency and length, and isolation challenges. As a result, these facilities may reject patients based on their positive colonization status. In 2023, the Tennessee Department of Health (TDH) conducted two containment-driven colonization screenings in response to a colonized patient receiving dialysis treatment for one month without their status being known to the facility. Methods: An initial point prevalence survey (PPS) was conducted to assess for ongoing transmission among dialysis patients. Patient screening was prioritized for the cohort of patients who received dialysis at the same time as the index patient (Cohort A). The screening was broadened to include patients dialyzed directly before Cohort A (Cohort B) by request of the Cohort B patients. A second PPS was conducted 7 weeks later, targeting the same cohorts. Specimens were collected through supervised patient self-collection of a skin swab from the axilla and groin. Flocked Eswabs were used for collection and transferred in Amies transport media to the Tennessee State Public Health Lab. The presence of C. auris was detected via Polymerase Chain Reaction (PCR). Results: Twenty-three patients (12 from Cohort A; 11 from Cohort B) were screened in the first PPS. One patient from Cohort A tested positive. This colonized patient was determined to be a known C. auris case first detected four months prior, but the patient’s status was never communicated to the dialysis facility from the discharging acute care facility. Eleven patients, excluding the previously identified positives, participated (9 from Cohort A; 2 from Cohort B) in the second PPS; no positives were identified. Discussion: The index patient and an additional patient identified by the PPS both received dialysis at this facility for up to 4 months without facility knowledge. These results suggest that the standard infection control practices at this dialysis facility were adequate to prevent the transmission of C. auris among dialysis patients on multiple shifts. Additionally, patient self-collection identified a known C. auris patient. Future TDH work includes further evaluating the risk of C. auris transmission and developing targeted infection prevention and control practices for the outpatient dialysis setting.

Background: The Uganda Ministry of Health (MoH) and implementing partners instituted an infection prevention and control (IPC) response strategy during the Uganda SVD outbreak in 2022 that involved rapid enhancement of screening capacity at HCFs. Rapid scale-up of screening for infectious diseases, such as SVD, is critical for early identification and triage of suspected or confirmed cases in HCFs. We describe the rapid deployment of a multimodal IPC strategy implemented in response to the SVD outbreak and the resulting impact on screening measures at HCFs. Methods: We implemented a multimodal IPC strategy in HCFs from five high risk districts to improve screening practices from November 2022–January 2023. The strategy included training health workers (HCWs) identified as IPC mentors; establishing screening areas; and providing screening supplies and communication materials. The three-day training utilized an MoH standardized training package with didactic and practice sessions. The mentors then cascaded screening information and skills to other HCWs through onsite trainings and mentorships and established screening areas. Baseline and endline (3 months after baseline) cross-sectional assessments were conducted using the MoH IPC Assessment Tool adapted from the WHO Ebola IPC Scorecard. The five main screening parameters assessed included presence of ≥ 1 meter distance between screener and the person screened, availability of a functional handwashing facility and infrared thermometer, correct record of each person’s temperature, and appropriate referral process for those suspected of having SVD to holding areas. IPC capacity was measured through the summation of each of these parameter results and calculated as an overall percentage. IBM SPSS Statistics 20 software was used for data analysis and a paired t-test done to determine any significant findings between mean scores (percentage) at baseline and endpoint. Results: A total of 296 IPC mentors were trained, screening information was cascaded to 3,899 HCWs, and screening areas were established in 1,135 HCFs. Based on the screening results from the MoH IPC assessment tool, capacity improved from 44% (SD=37) at baseline to 67% (SD=34) at endpoint. Screening capacity improved from baseline to endpoint among level II and public HCFs from 33% (SD=35) to 60% (SD=35) (p < 0 .05) and from 54% (SD=38) to 76% (SD=31) (p < 0 .05), respectively. Conclusion: Rapid implementation of a multimodal IPC strategy was successful in enhancing screening capacity across Uganda’s HCFs during a SVD response, which is critical for early identification of infected patients to interrupt transmission. This multimodal approach should be recommended for future response actions.

Stenotrophomonas maltophilia and Achromobacter xylosoxidans are emerging nosocomial, non-glucose fermenting, Gram-negative pathogens. In this nested case-control trial, independent predictors for S. maltophilia infections were hemodialysis and recent antibiotic usage (overall), while recent usage of fluoroquinolones, was independently associated with A. xylosoxidans infections. Infections were independently associated with multiple worse outcomes.

Background: Residence or recent stay in a long-term care facility (LTCF) is one of the most important risk factors for multidrug-resistant organism (MDRO) carriage and infection, making reliable identification of LTCF-exposed inpatients a critical priority for infection control day-to-day practice and research. However, because most hospital electronic health records (EHRs) do not include a dedicated field for documenting LTCF exposure, absent manual review of patient charts, identifying LTCF-exposed inpatients is challenging. We aimed to develop an automated, natural language processing (NLP)-based classifier for identifying LTCF exposure from clinical notes. Methods: We randomly sampled 1020 adult admissions from 2016-2021 across the 12-hospital University of Maryland Medical System and manually reviewed each admission’s history & physical (H&P) note for mention of LTCF exposure (Figure 1). After H&P pre-processing, we calculated feature representations for documents based on term frequencies and visually explored between-group (LTCF-exposed vs. LTCF-unexposed) feature differences. To predict LTCF status from the H&P notes, we trained and tuned a LASSO regression-based classifier on 70% of the data with 3-fold cross-validation and 1:1 up-sampling to address class imbalance. The final classifier was evaluated on the 30% held-out sample (not up-sampled), with calculation of the C-statistic (area-under-the-curve, AUC) with bootstrapped 95% confidence intervals, and construction of receiver-operating-characteristic and variable importance plots (R Version 4.3.2). Results: 7% (n=76 cases) of H&P notes documented LTCF exposure. In our visual analysis, the H&P words and phrases that were over-represented among LTCF patients had high face validity (Figure 2). The final LASSO-regression-based classifier achieved a C-statistic of 0.89 (95% CI: 0.80–0.98) on the held-out data for identifying LTCF exposure from the H&P notes (Figure 3). The most important model predictors (i.e., words) for distinguishing LTCF-exposed from LTCF-unexposed patients are reflected in Figure 4. The most important predictor-words of LTCF-exposure were “rehab,” “place,” “status,” “egd,” and “dementia.” Conclusion: In this multi-center study, even a simple NLP classifier demonstrated very strong discrimination for identifying LTCF exposure status from H&P notes, which could substantially reduce the manual review time required to identify LTCF-exposed inpatients. If automated in the electronic health record, it could also inform real-time MDRO screening decisions. Future research is planned to build more sophisticated classifiers using machine learning best practices, to build classifiers for additional MDRO risk factors, and to externally validate NLP classifiers on notes from an external healthcare system.

Background: The frequency of Staphylococcus aureus transmission in hospitals is unknown: symptomatic infection may occur months after transmission and colonization, and infection prevention efforts rely on indirect measurements, rather than direct detection of transmission events. We implemented a hospital-based S. aureus screening program, combined with whole genome sequencing of S. aureus surveillance and clinical cultures and data extracted from the electronic health record, to identify S. aureus clonal complex-, patient- and location-specific factors associated with S. aureus transmission in our health system. Methods: Screening S. aureus cultures were obtained at admission by nasal swab for adults admitted to Medicine, Transplant, Oncology and intensive care, and weekly by swab of nares, axilla and groin for children admitted to intensive care and Oncology at NYU Langone Health in New York City. All methicillin-resistant S. aureus (MRSA) from screening and clinical (blood, wound, sputum) cultures and all methicillin-susceptible S. aureus (MSSA) from screening and blood cultures underwent whole genome sequencing. Isolates from distinct patients with < 2 0 single nucleotide pair differences were considered genetically related. Electronic health data was extracted for descriptive statistics and for spatiotemporal plots to assess plausible transmissions. We used REDCap electronic data capture tools hosted at NYU Grossman School of Medicine and SAS software for data analysis to evaluate S. aureus transmissions between November 2022 and November 2023. Results: We analyzed 8,567 S. aureus isolates: including 6,552 screening cultures, 1,008 blood cultures, and 1,007 clinical cultures. We found 424 plausible S. aureus hospital transmissions using sequencing and electronic health data. Screening cultures identified 75% of transmissions that would have otherwise been missed with blood and clinical cultures alone. The majority of positive screening cultures isolated MSSA, but the proportion of transmissions due to MSSA differed by age. In children, MSSA colonization accounted for 62% of transmissions. In adults, only 15% of transmissions were due to MSSA colonization, whereas MRSA colonization accounted for 56% of transmissions. Analysis of adult MRSA isolates by clonal complex found that 45% of transmissions were due to CC8, higher than the 17% among isolates agnostic of transmissions. Emergency departments and the neonatal intensive care unit had the highest number of transmissions. Patients involved in transmissions had longer lengths of stay and frequent hospitalizations. Conclusions: A S. aureus screening program, coupled with genome sequencing and electronic health data, can identify patient group, hospital locations and clonal complexes that are at high risk for S. aureus transmissions.

We report 9 patients with invasive Bartonella infections, including 5 with endocarditis, who were diagnosed with microbial cell-free DNA next-generation sequencing and Bartonella serology studies. Diagnosis with plasma mcfDNA NGS enabled a faster clinical and laboratory diagnosis in 8 patients. Prompt diagnosis impacted antibiotic management in all 9 patients.