Background: Candida auris is an emerging threat to hospitalized patients and invasive disease is associated with high mortality. This study describes clinical and microbiological characteristics of nine patients identified with C. auris at Ohio State Wexner Medical Center discovered through active surveillance or clinical investigation and uses whole genome sequencing (WGS) to compare isolates. Methods: In November 2022, an active C. auris surveillance program was implemented to screen patients admitted to high-risk units (intensive care units and progressive care units). Bilateral axilla and groin swabs were obtained upon unit admission and, if positive, were submitted for C. auris polymerase chain reaction (PCR) with culture and sensitivity testing. Patients with a positive screening or clinical isolate from November 2022 to November 2023 underwent chart review for clinical characteristics, microbiologic data, and index admission information. For each isolate, DNA was extracted and WGS was performed. Core single nucleotide polymorphism (SNP) variation identified from the sequence data was used to infer genetic relationships among the isolates. Results: Nine patients were identified between November 2022 and November 2023. The clinical and microbiologic characteristics are summarized in Table 1. All patients were hospitalized at various acute care facilities across the state at least once in the preceding 12 months. C. auris was determined to be present on admission for 6 patients. For 5 of these patients, it was their first interaction with our healthcare system. Three patients were not in contact isolation for >3 days before C. auris was identified. Unit wide point-prevalence screening was completed in these cases and no evidence of transmission was found. WGS showed eight of the nine isolates were related with 28 or less core SNP differences between isolates (Figure 1). One isolate (8) was genetically distinct with >45000 core SNP differences. Five isolates were highly related with a range of 4-15 SNP differences. No temporal or spatial overlap at our institution was identified among these five patients. Conclusions: The active surveillance program identified several patients colonized with C. auris in addition to those found through clinical testing. Multiple risk factors for C. auris were identified with high patient mortality (67%). Majority of the isolates were closely related without association with a known outbreak or epidemiologic link, suggesting a possible diffuse common reservoir. Next steps with surveillance in acute care and long-term care facilities will be critical for early detection to halt transmission of this organism.

Although the practice of human sacrifice in the British Iron Age is mentioned by multiple authors, both ancient and modern, physical proof of such activity in the archaeological record is comparatively rare. At Winterborne Kingston, in Dorset, the skeletal remains of a young adult female found face down near the base of a cylindrical storage pit provides clear evidence of violent death in the later Iron Age. Analysis of the skeleton suggests an individual who led a hard-working life and who, having suffered an act of violence a few weeks before death, was killed, possibly with her hands tied, by a blade incision to the neck. Placement of the body further suggests that killing was enacted within the pit, execution as spectacle forming the final act in a larger ceremony involving the creation of an animal bone stack or platform.

OBJECTIVES/GOALS: Bronchiolitis is a major cause of PICU admission, yet identifying best practices is limited by the lack of existing databases containing the needed demographic and clinical variables. We used probabilistic linkage to join the Virtual Pediatric System (VPS) and Pediatric Health Information Systems (PHIS) databases to overcome this data barrier. METHODS/STUDY POPULATION: We performed a single site study joining VPS and PHIS data. These national databases contain clinical (VPS) and billing and resource use (PHIS) data. Limits on the use of patient identifiers (PI) for multi-center research, makes direct linkage techniques impossible. To demonstrate that probabilistic linkage can accurately link VPS and PHIS records, we obtained our single site VPS and PHIS records and linked them using probabilistic linkage without PI and compared this to a gold standard linkage created with PI. We also compared demographic features of linked and unlinked records to assess the ability of probabilistic linkage to create a representative sample. RESULTS/ANTICIPATED RESULTS: We obtained 920 VPS records of patients with bronchiolitis and linked 91% (839/920) to a PHIS record with 4 (0.5%) false-positive matches. Characteristics of linked and unlinked records are compared in Table 1. Comparison of probabilistically linked and unlinked records showed no difference in median age in years (0.7 [Interquartile range (IQR) 0.3-1.5] v 0.7 [IQR 0.2-1.5], p = 0.76), median number of complex chronic conditions (0 [IQR 0-1] v 0 [IQR 0-1], p = 0.16), median Pediatric Index of Mortality 3 severity of illness scores (-4.6 [IQR -4.7 – 4.4] v -4.6 [IQR -4.7 – 4.4], p = 0.44), median days of PICU stay (4 [IQR 3-6] v 4 [IQR 2-6], p = 0.36), proportion female ( 44% v 46%, p = 0.82), or proportion of patients intubated (28% v 24%, p = 0.41). DISCUSSION/SIGNIFICANCE: Probabilistic linkage creates an accurate combined VPS-PHIS database. Extending our methodology to join data from all 38 hospitals contributing to VPS and PHIS will allow creation of a large database containing the demographic, treatment, and outcome data needed to enable Comparative Effectiveness Research of bronchiolitis care.

Background: Multidrug-resistant organisms (MDROs) are increasingly implicated in nosocomial outbreaks worldwide. We evaluated whole-genome sequencing (WGS) as an adjunctive epidemiological tool to identify infection clusters and MDRO transmission in the healthcare setting. Methods: Clinical isolates of carbapenem-resistant Enterobacterales (CRE) from July 1, 2021, to June 30, 2022, underwent Illumina WGS. Assembled genomes were taxonomically classified with GTDB-Tk software and were typed using multilocus sequence typing (MLST). Average nucleotide identity (ANI) was calculated between genomes. Numbers of differences among core single-nucleotide polymorphisms (SNPs) were calculated for pairs within taxonomic groups, and the data were evaluated in the context of patient dates and locations of care obtained from the electronic medical record. Results: In total, 39 CRE isolates underwent WGS (Fig. 1). Klebsiella pneumoniae represented the largest number of isolates (n = 18). Using MLST, 2 distinct groups of K. pneumoniae were identified (ST307 and ST258) with 5 and 4 isolates, respectively (Fig. 2). Within ST307, SNP differences ranged between 8 and 115. 3 isolates (CRE8, CRE10, and CRE12) were collected within 4 weeks of each other and had ≤26 pairwise SNP differences. Notably, CRE8 and CRE10 were located on the same unit at the same time and used the same MRI scanner on the same day. CRE35 had >95 SNP differences and was admitted 8 months prior to others in ST307 but had surgery in the same OR as CRE8. Within ST258, pairwise comparison of samples revealed 139–588 SNP differences. CRE21, CRE31, and CRE33 had SNP differences of ≤150. These patients were in the same hospital room (CRE33 and CRE21) and unit (CRE31 and CRE33), but they did not overlap temporally. CRE37 had >580 SNP differences, with no overlap in hospitalization dates or locations with other patients. Conclusions: Two closely related K. pneumoniae isolate populations were identified using WGS. Strong temporal and spatial commonalities were identified among isolates with few SNP differences. Isolate pairs with intermediate SNP differences shared spatial commonalities, suggesting possible indirect transmission between patients. No common exposures were identified for pairs with large numbers of SNP differences. WGS is an evolving tool to detect outbreak clonal populations of MDRO not identified through traditional epidemiologic techniques. WGS can provide insight into transmission patterns and the role of environmental contamination in propagating these nosocomial infections. More studies are needed to define the role and clinical significance of isolates with intermediate SNP differences in transmission of these pathogens between hosts and the healthcare environment.

Disclosures: None