bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-1313. Large Outbreak of Staphylococcus aureus and Bacillus cereus Caused by Ready-to-Eat Meals in Aomori, Japan
Authors: Eita Mizue , Yahata Yuichiro , Nakamura Natsuko , Fujita Keiichiro , Saito Masato , Matsukura Kaori , Takagi Hiromi , Nakamura Mizuki , Shimada Tomoe , Ishii Atsuko , Kudou Masanobu , Sunagawa Tomimasa 
Published: January 2025

Abstract

Background
Ready-to-eat meals are a vehicle of multijurisdictional outbreaks of foodborne diseases worldwide. Ekiben is a type of ready-to-eat meal commonly sold at train stations and occasionally at markets in Japan. On September 17, 2023, the Hachinohe City Public Health Center (HCPHC) received numerous complaints from consumers in several prefectures who had eaten ekiben produced by Company A in Hachinohe, Aomori, Japan.

Methods
In collaboration with HCPHC, we conducted an epidemiological investigation, traceback/traceforward investigation, and an inspection of Company A. The local public health authorities performed microbiological tests of food and stool samples.

Results
A total of 554 symptomatic cases were identified in 29 prefectures. The highest proportion of symptoms was diarrhea (86%), followed by vomiting (61%), nausea (59%), and stomachache (51%). Company A produced 67 lunchboxes of which 23 types of lunchboxes occurred cases. 23 lunchboxes contained seafood as an ingredient but no common ingredients except for rice. The rice was self-produced and/or outsourced from Company B. Company A received triple the number of usual orders from retailers and trading companies due to an “Ekiben Fair” held on September 15 and 16. Company A could not prepare enough steamed rice for such an event on its own, so it outsourced the production of some rice to Company B, which shipped the rice at temperatures ranging from 42°C–49°C. Staphylococcus aureus with enterotoxin and Bacillus cereus with enterotoxin were detected from stool samples as well as steamed rice and other food samples with sufficient amounts of bacteria to cause the disease. Company A did not have an appropriate HACCP plan, operation manual, response plan, or processing records. The company had no records of hygiene training, hygiene education, health checks, or hand-injury records for its temporary workers. We concluded that the likely causative food was steamed rice that had been shipped at an improper storage temperature, and processing the lunchboxes.

Conclusion
We recommended that Company A store rice at the proper temperature, implement an appropriate HACCP plan, create a standard operation manual, maintain processing records, separate clean and contaminated areas, and prepare a response plan in case of unusual situations.

Disclosures
All Authors: No reported disclosures
P-1320. HAISeq: Monitoring Emerging and Novel Gram-Negative Antimicrobial Threats from Healthcare Settings in the United States with Publicly Available NCBI BioProject Data
Authors: Moser Kara A , Kent Alyssa , Hagey Jill V , McAllister Gillian A , Aubert Rachael , Halpin Alison L 
Published: January 2025

Abstract

Background
Gram-negative healthcare-associated infections (HAIs) and antimicrobial resistance (AR) cause considerable morbidity and mortality in the United States. Whole genome sequencing (WGS) has become a critical methodology to describe HAIs, providing important contextual information on resistance genes and relatedness. It is essential that public health agencies leverage large amounts of WGS data quickly for public health action, and that data can be accessible across jurisdictions.

Methods
In advance of an influx of resources to state public health laboratories for HAI/AR WGS capacity, CDC’s Division of Healthcare Quality Promotion (DHQP) established the HAISeq Umbrella BioProject in the National Center for Biotechnology Information’s Short Read Archive as a centralized repository for WGS data generated by DHQP and partners. Data submitted is from CDC’s Antimicrobial Resistance Laboratory Network, surveillance projects, and outbreak investigations.

Results
The gram-negative-specific BioProject within the HAISeq Umbrella currently contains 6.5TB of WGS data, representing &gt; 20,000 gram-negative isolates, ∼40 genera, and &gt; 450 unique AR genes. While DHQP priorities are heavily reflected in represented genera (Acinetobacter, Pseudomonas, Klebsiella, Escherichia) and gene targets (e.g., &gt;10 carbapenemase families), the dataset also represents hundreds of minor frequency species and genes captured from the above sequencing efforts. DHQP uses bimonthly data pulls to detect potential novel and emerging HAI/AR genetic threats. Examples include identification of novel carbapenemase variants (e.g., 23 variants from all “Big 5” groups), variants that convey unexpected phenotypes to treatment options (e.g., carbapenem susceptible but ceftazidime-avibactam resistant), and rare gene/organism combinations (e.g., blaOXA-48-like genes in Acinetobacter baumannii). Data are also used to rapidly provide feedback to public health laboratories on data quality issues. Finally, these data help inform national HAI/AR sequencing priorities.

Conclusion
This publicly available dataset, alone and in combination with traditional testing data, allows for both federal and state public health labs to leverage WGS for public health action while maintaining data privacy.

Disclosures
All Authors: No reported disclosures
P-1347. Characterizing Atypical Antibiotic Non-Susceptibility Features of Emergent U.S. Carbapenem-resistant Acinetobacter baumannii Lineages
Authors: Graffice Emma , Siam Md Hasanul Banna , Calix Juan , Amerson-Brown Megan 
Published: January 2025

Abstract

Background
Due to elevated genetic divergence between different Carbapenem-resistant (CR) A. baumannii (Ab) lineages, CRAb isolates belonging to clonal groups (CGs) currently emerging in the U.S. may display traits that differ from those of unrelated international CGs. Variations in CG-associated physiology could especially affect the choice and interpretation of antimicrobial susceptibility tests (AST) for these multidrug resistant lineages.

Methods
We integrated multimodal AST and comparative genomic analysis of CG108, CG406, and CG499 isolates identified in two U.S. cities since 2017. Lineage-specific resistance features were queried among genomes of isolates from other U.S. locations. We further investigated a unique sulfonamide (SXT) heteroresistance trait via mutational analysis.

Results
Most antibiotic non-susceptibility was attributable to conventional, lineage-independent resistance determinants on mobile genetic elements. In contrast, a FtsI A515V polymorphism shared among CG108 genomes appears to confer carbapenem resistance independent of carbapenamases, while genomes of various CG406 CRAb isolates lacked any readily identifiable CR determinant. We observed antibiotic-specific heteroresistance against sulbactam (SAM) and imipenem among CG108 isolates and against SXT among CG499 isolates. Integrity of the wzc gene in a CG499 isolate was necessary for high-molecular weight capsule polysaccharide (KPS) production and SXT heteroresistance. Despite lacking any conventional resistance determinants, the wzc-deficient mutant and all other CG499 isolates displayed greater resistance to SXT compared to most susceptible Ab isolates.

Conclusion
We describe AST features unique to emerging CRAb CGs and independent of conventional extrinsic resistance genes. CG499 SXT heteroresistance appears to rely on the ability to produce high-molecular weight KPS, though another unidentified mechanism also contributes to decreased susceptibility compared to wild-type. We propose ongoing surveillance efforts must recognize lineage-related variations to best tailor new strategies against the evolving nature of CRAb disease.

Disclosures
Megan Amerson-Brown, PhD, Selux diagnostics: Grant/Research Support
P-1351. Occurrence of b-lactamases among Enterobacterales isolates from United States Hospitals in a 10-year period: Report from the International Network for Optimal Resistance Monitoring (INFORM) Program
Authors: Castanheira Mariana , Doyle Timothy , Hubler Cory , Deshpande Lalitagauri , Mendes Rodrigo E , Sader Helio S 
Published: January 2025

Abstract

Background
β-lactamase-production in Enterobacterales challenge the use of β-lactams, the most broadly used and versatile class of antimicrobial agents. The INFORM program surveys β-lactamases and the activity of ceftazidime-avibactam in US hospitals. We analyzed 10 years of data from that study.
Yearly distribution of most common β-lactamases among E. coli (EC) and K. pneumoniae (KPN) isolates collected during 2013-2022 in US hospitals

Methods
90,956 Enterobacterales isolates were consecutively collected in 22 US hospitals participating in the INFORM program during 2013 to 2022. Susceptibility testing was performed and interpreted according to CLSI. E. coli (EC) and K. pneumoniae (KPN) displaying MICs ≥ 2 mg/L for two of: ceftriaxone, ceftazidime, cefepime or aztreonam; or carbapenem-resistant Enterobacterales (CRE; resistant to meropenem or imipenem) were evaluated for the presence of β-lactamase genes. Genetic analysis was performed by microarray/PCR (2013-2015) or whole genome sequencing (2016-2022).
Yearly distribution of CRE isolates collected during 2013-2022 in US hospitals

Results
ESBLs were detected among 2,334/2,691 (15.6% of 14,969 overall non-CRE isolates) EC and 964/1,051 (13.8% of 6,988) KPN. A decline in EC displaying the phenotypic criteria and CTX-M-15-like isolates (12.6% in 2021 and 8.3% overall in 2022; Figure 1) was noted in 2022. The most common ESBL in both groups was CTX-M-15-like (10.5/58.3% of the EC overall/characterized and 11.0/73.4% of the KPN). SHV ESBLs had a steady decline among KPN since 2015. CRE isolates declined steadily from 1.6% in 2013 to 0.8% in 2022 (Figure 2). Carbapenemase-positive isolates also declined from 1.3% to 0.6%, with a decline in KPC producers but an increase in isolates producing NDM that were initially detected in 2015 and range from 10-16 isolates in the last 3 study years. Ceftazidime-avibactam and the carbapenems are the most active agents against β-lactamase-producing isolates (Figure 3).
Activity of ceftazidime-avibactam and comparators against main β-lactamase groups

Conclusion
Changes in β-lactamase-producing isolates and its susceptibility profiles should be closely monitored in a local and global level since it impacts patient treatment, but longitudinal data such as this information is scarce.

Disclosures
Rodrigo E. Mendes, PhD, GSK: Grant/Research Support
501. Impact of Implementation of World Health Organization (WHO) National Action Plans (NAP) on Antibiotic Rates: A Time Series Analysis of 38 Countries
Authors: Miner Tate , Callaway Kim Katherine , Rothenberger Scott , Chaudhry Shanzeh , Tadrous Mina , Suda Katie J 
Published: January 2025

Abstract

Background
Antimicrobial Resistance (AMR) poses a major threat to global health. In 2015, the World Health Organization (WHO) advised that member nations should develop National Action Plans (NAPs) to improve antibiotic stewardship and decrease AMR. However, the association between NAP implementation and antibiotic use is unknown. The objective of this study, therefore, was to examine post NAP-implementation changes in antibiotic utilization.Figure 1:Relative change in the population-based antibiotic rate after 2 years of implementation of National Action Plans (NAP)

Methods
We conducted a longitudinal repeated cross-sectional study of antibiotic purchases leveraging IQVIA’s MIDAS database. Our sample included 38 countries which implemented NAPs from June 2013 to January 2018. Quarterly purchases were reported in standardized units (1 pill/capsule/vial/5mL oral liquid) per 1 million population. We conducted an interrupted time-series analysis using mixed effects negative binomial models with a log link to assess level and trend changes in the antibiotic purchasing rate in the 8 quarters after each country’s NAP implementation, relative to 8 quarters pre-implementation. We included sinusoidal terms to account for seasonality, as well as random effects to estimate country-specific changes in rates after 8 quarters.

Results
Across all countries, the average level change post-NAP implementation was .03 log units (p=.44), and the average trend decreased by -.0014 log units per quarter (p=.72). After two years, the overall relative change in the purchasing rate was 1.9% [-7.8, 12.5], with country-specific effects ranging from -38.6% to 216% (See Figure 1). Only 4 countries (Norway, Jordan, South Africa, and Indonesia) experienced significant decreases.

Conclusion
Implementation of the NAP was not associated with overall changes in antibiotic purchasing two years later. The findings of this study may be useful for evaluating the effectiveness of these policies in terms of their stated objectives as well as identifying factors that led to the success of those countries that did observe decreases in antibiotic utilization.

Disclosures
All Authors: No reported disclosures
P-1361. Cefiderocol Activity against Pseudomonas aeruginosa, Including Resistant Subsets and Isolates Carrying Carbapenemase β-lactamase Genes, from United States Hospitals (2020–2023)
Authors: Mendes Rodrigo E , Maher Joshua , Hubler Cory , Scullin Abigail , Karr Maura , Kimbrough Hank , Castanheira Mariana 
Published: January 2025

Abstract

Background
Pseudomonas aeruginosa (PSA) possess various intrinsic treatment-limiting resistance mechanisms, leading to decreased antibiotic permeability, and also the ability to acquire resistance. Cefiderocol (FDC) is a siderophore cephalosporin that uses the iron transport systems of Gram-negative bacteria to optimize cell entry. The activity of FDC and comparator agents were evaluated against PSA causing infections in US hospitals, including resistant subsets, as part of the SENTRY Antimicrobial Surveillance Program.

Methods
4,400 PSA were collected from 36 sites in the US in 2020–2023. Susceptibility (S) testing was performed by broth microdilution with cation-adjusted Mueller-Hinton broth (CAMHB) for comparators and iron-depleted CAMHB for FDC. CLSI/FDA criteria were applied. Isolates with imipenem (IMI) or meropenem MIC ≥4 mg/L (nonS by CLSI) were screened for β-lactamase genes. Multidrug resistance (MDR) was defined as nonS to ≥3 drug classes by CLSI; whereas, extensively drug resistance (XDR) was defined as nonS to all but 2 or fewer drug classes.

Results
14.6% (643/4,400) and 4.7% (206/4,400) PSA isolates were MDR and XDR, respectively. 22.3% (980/4,400) PSA were carbapenem-nonS, with only 9 (0.9%) strains carrying carbapenemases. FDC and β-lactam/β-lactamase inhibitor (BL/BLI) combinations showed S of &gt; 95% against all PSA, except for piperacilin-tazobactam (79.9%S) (Table). FDC (90.8–99.4%) showed MIC50 of 0.12 mg/L and MIC90 of 0.5–1 mg/L against MDR, XDR and carbapenem-nonS isolates, whereas BL/BLI showed S of 2.9–90.2%. FDC (100%S) inhibited all PSA carrying carbapenemases at the CLSI S breakpoint of ≤2 mg/L. Other comparators showed S of &lt; 35% against the latter subset. FDC (MIC50/90, 0.12/0.5 mg/L; 96.8–99.4%S) had MIC 4- to 8-fold lower than IMI-relebactam (MIC50/90, 1/2 mg/L; 90.0%S) and cetolozane-tazobactam (MIC50/90, 1/4 mg/L; 90.9%S), which were also active against carbapenem-nonS PSA absent of carbapenemase genes.

Conclusion
FDC showed potent and cosistent activity against PSA clinical isolates from US hospitals, including resistant subsets and those with or without carbapenemase genes. These data demonstrate FDC activity against PSA resistant subsets, for which antibiotic treatment options are limited.

Disclosures
Rodrigo E. Mendes, PhD, GSK: Grant/Research Support
P-1362. Cefiderocol Activity against Carbapenem-resistant Acinetobacter baumannii-calcoaceticus complex, Including Molecularly Characterized Clinical Isolates, Causing Infections in United States Hospitals (2020–2023)
Authors: Mendes Rodrigo E , Scullin Abigail , Kimbrough Hank , Karr Maura , Maher Joshua , Hubler Cory , Castanheira Mariana 
Published: January 2025

Abstract

Background
Multidrug-resistant (MDR) Acinetobacter baumannii-calcoaceticus complex (ACB) have gained attention as an important clinical challenge in the last decades, due to its ability to develop resistance to front-line antibiotics. Cefiderocol (FDC) is a siderophore cephalosporin that uses the iron transport systems of Gram-negative bacteria to optimize cell entry. The activity of FDC and comparators were evaluated against ACB causing infections in US hospitals, including resistant subsets, collected as part of the SENTRY Antimicrobial Surveillance Program.

Methods
1,786 Acinetobacter spp. were collected from 36 sites in the US during 2020–2023. Susceptibility (S) testing was performed by broth microdilution with cation-adjusted Mueller-Hinton broth (CAMHB) for comparators and iron-depleted CAMHB for FDC. CLSI/EUCAST/FDA criteria were applied. Isolates with imipenem or meropenem MIC ≥4 mg/L (nonS by CLSI) were screened for β-lactamase genes.

Results
ACB comprised 80.5% (1,438/1,786) of isolates collected, and all 405 carbapenem-nonS isolates were identified as ACB. Carbapenemase genes were detected in 86.9% (352/405) of carbapenem-nonS ACB, and blaOXA-23 (59.9%; 211/352) prevailed, followed by blaOXA-24 (25.6%; 90/352), and blaOXA-72 (9.4%; 33/352). FDC (93.6–98.8%S) had MIC50 of 0.12 mg/L and MIC90 of 1 mg/L against all Acinetobacter spp. and the ACB subset (Table). Comparators had limited activity against these isolates (66.5–77.1%S), except for colistin (COL) (95.7–96.2%S). FDC (97.0–97.7%S by CLSI) had MIC50 of 0.25 mg/L and MIC90 of 2 mg/L against carbapenem-nonS ACB and those carrying carbapenemases. Only COL was also active against these 2 resistant subsets. FDC (97.2–100%S by CLSI) MIC90 of 2 mg/L, 1 mg/L and 0.5 mg/L were obtained against ACB carrying blaOXA-23, blaOXA-24, and blaOXA-72, respectively. Isolates carrying other carbapenemases were inhibited by FDC MIC of ≤2 mg/L, except for 1 strain with blaOXA-23 and blaNDM-1 (MIC, 8 mg/L).

Conclusion
This study demonstrates the MDR nature of ACB causing infections in US hospitals, and FDC as an active agent against these isolates, regardless of resistance genotype. These in vitro data suggest FDC as an important option for the treatment of infections caused by MDR ACB.

Disclosures
Rodrigo E. Mendes, PhD, GSK: Grant/Research Support
P-1417. High Rates of Patient Directed Discharge Associated with Incomplete Treatment and Rehospitalization in People Hospitalized with Serious Injection Related Infections: The CHOICE+ Cohort
Authors: Rosenthal Elana S , Kattakuzhy Sarah , Omari Habib , Stevens Jasmine , Derenoncourt Meghan , Vaish Ishan Kumar , Flores Hannah E , Fujita Ayako Wendy , Raman Sumitha , Steck Alaina , Kuo Irene , Catalanotti Jillian S , Carpenter Joseph E , Reece Becky , Traver Edward C 
Published: January 2025

Abstract

Background
People who inject drugs have high rates of patient directed discharge (PDD). In a cohort of patients hospitalized for serious injection related infections (SIRI), we aimed to assess the factors leading to PDD and the influence of PDD on rehospitalization.
Characteristics of study participants

Methods
CHOICE+ is a multisite retrospective cohort study of adults hospitalized at four healthcare systems with SIRI due to injection opioid use between 1/1/2018 and 3/31/2022. Data were collected by abstraction of the electronic medical record and were analyzed by chi-square and multivariable logistic and linear regression.
Factors associated with patient directed discharge

Results
Of 1645 patients, 1180 (72%) had a planned discharge and 465 (28%) had a PDD. PDD was associated with younger age (p&lt; 0.001), white race (p=0.018), and documented opioid withdrawal (p&lt; 0.001). PDD was less likely in patients on medication for opioid use disorder (MOUD) during hospitalization (p&lt; 0.001) or who received consultations by infectious diseases (p&lt; 0.001), social work (p=0.04), or addiction medicine (p=0.003).
Compared to those with planned discharge, patients with PDD were less likely to have completed antibiotics at the time of discharge (7% vs 60%; p&lt; 0.001), and 64% left without a plan for antibiotic completion. Patients with PDD were more likely to be readmitted within a year (57% vs 52%; p=0.015), and more likely to have a first readmission due to an infection (81% vs 56%; p&lt; 0.001). Time to readmission was significantly shorter among patients with PDD (15 vs 65d; -41.5 days, p&lt; 0.001).
Post-Hospitalization Antibiotic Plan by Discharge Status

Conclusion
Among people hospitalized with SIRI, we found high rates of PDD associated with insufficient treatment of OUD, evidenced by withdrawal, lack of MOUD, and not receiving an addiction consultation. PDD was consequently associated with higher rates of readmission due to infection and shorter time to readmission, possibly due to discharge without a plan to complete antibiotics. To improve outcomes and reduce readmissions among people with SIRI, efforts to address OUD during hospitalization are crucial, and could reduce PDD. Regardless, given high rates of PDD in this population, strategies to facilitate continuity of antibiotics - including contingency plans for oral or long-acting regimens - may be critical to ensuring resolution of SIRI and improving long-term outcomes.
Risk of Readmission within 1-Year Based on Discharge Status

Disclosures
Elana S. Rosenthal, MD, Gilead Sciences: Grant/Research Support|Merck: Grant/Research Support
P-1420. Tracking Shadows: Loss to Follow-up in Persons Living with HIV
Authors: Bhatia Mehak , Carrington William , Touleyrou Lauren , Newman Gretchen 
Published: January 2025

Abstract

Background
During the year 2020, HIV viral suppression was 89.4% in clients throughout the United States who receive care through the Ryan White HIV/AIDS program (RYHAP). This was a significant increase compared to 69.5% in 2010. Likewise, Wayne State University (WSU) Tolan Park Infectious Disease Clinic, which is also funded by RYHAP noted a 5% increase in the rate of viral suppression in 2020 compared to the previous year. Eighty-six percent of Tolan Park clients across all Ryan White programs were virally suppressed, eighty-seven percent of women and youth were virally suppressed. However, there was a decline in the overall patient pool in 2019. The goal of this study was to locate those lost-to-care as part of the WSU Tolan Park clinic.

Methods
Clinicians reviewed a list of clients who were lost-to-care during 2019. These clients were individually called by nurse practitioners, patient advocates or early intervention staff (EIS) to re-engage in medical care. The quality improvement team then discussed feedback from staff and clients regarding barriers to medical care.

Results
We contacted a total of 310 clients. Out of these, 40 (13%) were lost-to-care. Among the remaining clients, 95 (31%) were deceased, 64 (21%) were in-care at other clinics, 63 (20%) were currently in-care at Tolan park clinic, 41 (13%) had confirmed clinic appointments and 7 (2%) were out-of-state or incarcerated. Of the 40 clients returned to care at the Tolan Park clinic, route cause analysis revealed the main barriers to care including poor mental health, lack of transportation, schedule conflicts, relocation, poor financial resources, inadequate medication adherence and clinic fatigue.

Conclusion
We report a significant number of patients who were lost-to-care at the WSU Tolan Park clinic. Our patients continue to experience poor mental health, poor medication adherence and several socioeconomic barriers that limit their access to continuity of care. Our results highlight the need for better tracking services and strategies to minimize the loss to follow-up in HIV clinics.

Disclosures
All Authors: No reported disclosures