bluuebunny/crossref_metadata_2025_split huggingface dataset:
637. Stable bloodstream infection rates despite rising colonization: Insights from a hospital system using in-house PCR screening for Candida auris
Authors: Rosa Rossana M , Rosello Gemma , Manzanillo Kelley , Martinez Octavio , Abbo Lilian M 
Published: January 2025

Abstract

Background
Candida auris (C. auris) is spreading in the United States at a rapid pace. At our facilities, risk-based admission screening for colonization with C. auris using PCR has been a cost-effective tool for guiding infection prevention (IP) practices. We describe the observed trends in incidence of detection of colonization present on admission and hospital-onset cultures at our facilities since deploying in-house PCR testing.Figure 1:A. Candida auris 2-step screening process B: Sample Candida auris screening questionnaire

Methods
Study conducted at an integrated healthcare system in Miami, Florida, consisting of a large tertiary care center, three community hospitals and one inpatient rehabilitation hospital. The study period went from August 2021 to December 2023. In August 2021 we implemented admission screening for C. auris with PCR performed in-house. Screening criteria, testing and isolation protocols are presented in Figure 1A-B. Patients testing negative on admission were not routinely re-tested. Joinpoint regression was used to estimate changes in the incidence rates of C. auris newly present on admission surveillance (CA-POA), hospital-onset (HO) clinical cultures from any source and bloodstream infections (BSI). Definitions used are presented in Table 1.

Results
We identified 292 patients with CA-POA, for a crude rate of 9.1 per 10,000 patient-admissions. Between August 2021 and June 2023, the monthly percent change in the incidence rate of CA-POA significantly increased by 4.9% (95% CI 2.6-7.2; p&lt; 0.01) and decreased by 17.4% (95% CI -30.8 to -1.5; p=0.03) between July 2023 and December 2023. There were 124 patients with HO clinical cultures, including 72 hospital-onset BSIs, for a crude BSI rate of 0.59 per 10,000 patient-days. There were no statistically significant changes in the trends of incidence of these infections during the study period. Incidence rates for the different outcomes of interest are displayed in Figure 2A-2D.
Incidence rates for outcomes of interest

Conclusion
We found that despite rising rates of patients newly identified as already colonized with C. auris upon admission, the rates of HO cultures and most importantly of bloodstream infections have remained stable at our facilities. Admission screening using in-house PCR can lead to a more precise deployment of IP resources, mitigation of horizontal transmission and raising public health awareness on spread occurring outside hospitals.

Disclosures
All Authors: No reported disclosures
P-1898. Reduction of Blood Culture Contamination Rates and Associated Healthcare Costs Through Implementation of Certified Phlebotomist-Drawn Blood Cultures at a Community Teaching Hospital
Authors: Mishra Shikha , Valdez Michael , Mejia Danna , Vickers Adonica , Johnson Royce H , D’Assumpcao Carlos M , Kuran Rasha , Fang Michelle 
Published: January 2025

Abstract

Background
Blood culture contamination (BCC) is a drain on healthcare resources, with clinical implications such as delayed diagnosis. At Kern Medical (KM), a safety net teaching hospital in Bakersfield, CA, BCC in some areas had continually exceeded the 3% recommended maximum, with 59% of new positive blood cultures per patient representing contamination in early 2023. In response, a quality improvement initiative was launched in 2023 to reduce BCC through certified phlebotomist-drawn blood cultures (PDBC).

Methods
A retrospective cohort study was conducted to assess the clinical and financial impact of BCC reduction through PDBC. Any blood culture with growth of a common commensal organism during the first 2 months of 2024 was reviewed for attributable hospital length of stay (LOS) and ED, laboratory, procedure and pharmacy resources associated with BCC. Patients were excluded if blood culture growth was indicative of true infection or if the patient was still admitted at the time of review or transferred to another hospital. Costs were calculated based on literature and institution-specific charges.

Results
BCC was identified in 35 patients over the study period, with coagulase-negative Staphylococcus (CoNS) species isolated in 71% of patients and polymicrobial growth in 34% of cases. Forty percent of patients had been admitted with a non-infectious principal diagnosis, and 14% of patients had been discharged at the time of blood culture positivity and were readmitted or called back to the ED for management of possible bacteremia. Transthoracic echocardiogram had been performed for assessment of infective endocarditis in 34% of all patients and 40% of patients with CoNS prior to final identification of the blood culture isolate(s), which required 5.5 days on average. Sixty-six percent of patients received vancomycin, including 43% of patients admitted for noninfectious diagnoses. Twenty-three percent of patients had new or additional LOS due to BCC, with an average of 1.4 days. The average additional cost associated with a BCC event at KM was $2931.

Conclusion
Given that BCC rates decreased at KM from 4.6% with non-certified phlebotomy staff collection compared to 1.2% with certified phlebotomist collection, introduction of PDBC resulted in an estimated cost avoidance of $778,596 per year.

Disclosures
All Authors: No reported disclosures
645. Rapid Versus Conservative Tuberculosis De-isolation Policy Impact Assessment: Province-wide Retrospective Review of 2017-2020, British Columbia, Canada
Authors: Alhekail Othman Zeyad O , Singh Navneet , Hansen Elisabeth , Johnston James , Cook Victoria J , Connors William J 
Published: January 2025

Abstract

Background
Tuberculosis (TB) remains a significant global health threat. Upon diagnosis, patients with pulmonary TB are required to undergo specific isolation precautions to prevent further disease transmission. Current practice typically mandates isolation for at least two weeks post-diagnosis, with extended periods for those found to have positive sputum acid fast bacilli (AFB) smear results. The most recent Canadian Tuberculosis Standards (2022) and other international groups have suggested that the decision to discontinue TB airborne isolation should be made based on length of effective treatment rather than bacteriological endpoint (i.e. Sputum AFB results and culture results).
Sputum-based (Conservative) de-isolation determination

Methods
This is a retrospective analysis of newly diagnosed drug susceptible pulmonary TB cases between 2017 and 2020 in British Columbia, Canada. By comparing rapid (defined in Table 1) and conservative (defined in Table 2) isolation determination policies, and estimating recommended isolation periods for each, we aim to quantify isolation periods and assess whether adopting the rapid de-isolation determination protocol would significantly reduce airborne isolation durations.
Treatment based (Rapid) de-isolation determination

Results
We identified a total of 952 cases with drug susceptible pulmonary TB. Among the 952, the mean age was 54 years (SD 22). With regards to sputum AFB smear status, 351 (37%) had a negative AFB smear at baseline and 355 (37%) remained sputum AFB smear positive for over 90 days (did not meet conservative de-isolation criteria). Among the remaining 246 cases, 82 converted their AFB smear status to negative within less than 28 days from the first positive sputum AFB smear sample. Based on sputum AFB smear status alone, we found that rapid de-isolation determination would have resulted in a median of 10 (IQR 62) fewer days of isolation.

Conclusion
Adopting a rapid de-isolation determination protocol would result in substantial reductions of isolation durations for patients with drug-susceptible pulmonary TB. Updated evidence-based TB de-isolation guidelines emphasizing effective treatment duration, such as the new recommendation from the National TB Coalition of America, can significantly reduce patients' harm and health system costs of unnecessarily prolonged isolation.

Disclosures
All Authors: No reported disclosures
P-1948. Differential Patterns of Protection from Natural Infection against SARS-CoV-2 Reinfection in the Pre-Omicron and Omicron Eras
Authors: Chemaitelly Hiam , Ayoub Houssein H , Abu-Raddad Laith J 
Published: January 2025

Abstract

Background
SARS-CoV-2 infection protection against reinfection can be compromised by emergence of immune-evasive variants.

Methods
A national, matched, test-negative, case-control study was conducted on Qatar's population between February 5, 2020-February 12, 2024, to assess the level and durability of protection offered by omicron infection against omicron reinfection, compared to the protection provided by pre-omicron infection against pre-omicron reinfection. Subgroup and sensitivity analyses were performed.

Results
Effectiveness of pre-omicron infection against pre-omicron reinfection was 81.1% (95% CI: 80.4-81.8%). Effectiveness was 81.3% (95% CI: 80.6-82.1%) in the first year after the previous infection and 79.5% (95% CI: 77.1-81.5%) thereafter. In contrast, effectiveness of omicron infection against omicron reinfection was only 53.6% (95% CI: 52.1-55.0%) and demonstrated rapid waning. Effectiveness declined from 81.3% (95% CI: 79.6-82.9%) within the first 3-6 months post-infection to 59.8% (95% CI: 57.8-61.7%) in the subsequent 3 months, further dropping to 27.5% (95% CI: 22.7-32.0%) within the next 3 months, and reaching only 4.8% (95% CI: -2.7-11.8%) after one year. Effectiveness against symptomatic reinfection and for both unvaccinated and vaccinated individuals mirrored these patterns. Effectiveness of infection in preventing severe, critical, or fatal COVID-19 upon reinfection remained nearly 100% in both pre-omicron and omicron eras, showing no signs of waning over time.

Conclusion
SARS-CoV-2 natural immunity shows a dynamic interplay between host immunity and viral evolution, resulting in contrasting reinfection patterns before and after omicron emergence. These patterns suggest a shift in evolutionary pressures, with intrinsic transmissibility driving adaptation pre-omicron and immune escape becoming dominant post-omicron.

Disclosures
All Authors: No reported disclosures
P-2002. Incidence and Risk of COVID-19 Hospitalization Among Unvaccinated Children
Authors: Zerbo Ousseny , Timbol Julius , Hansen John R , Goddard Kristin , Layefsky Evan , Ross Pat , Fireman Bruce , Nguyen Dao , Greenhow Tara L , Klein Nicola P 
Published: January 2025

Abstract

Background
Although most children often experience mild illness following SARS-CoV-2 infection, some can develop severe disease requiring hospitalization, admission into an intensive care unit (ICU), or die.

Methods
Children aged 0 - &lt; 18 years, members of Kaiser Permanente Northern California (KPNC), an integrated healthcare organization with more than 4 more million members, were followed from March 1, 2020, until the earliest occurrence of: chart-confirmed COVID-19 hospitalization, disenrollment from KPNC, age 18 years, receipt of COVID-19 vaccine, death, or study end (December 31, 2022). We calculated the incidence rate of hospitalization by SARS-CoV-2 variant period and by age group. We determined risk factors for hospitalization using Poisson regression. We also conducted descriptive analyses of hospitalized cases.

Results
Among 1,107,799 children, 423 were hospitalized for COVID-19 during follow-up. The incidence of hospitalization increased with each new SARS-CoV-2 variant and was highest among children aged &lt; 6 months. Among the &lt; 6-month-olds, the incidence rate per 100,000 person-months was 7 during pre-delta, 13.3 during delta and 22.4 during omicron. Black (RR= 2.05, 95% CI: 1.33 – 3.16) and Hispanic children (RR = 1.82, 95% CI: 1.34 – 2.46) and children with any comorbidities were at high risk of hospitalization (RR = 3.81, 95% CI: 2.94 – 4.95). Overall, 20.3% of hospitalized children were admitted to an intensive care unit (ICU), but ICU admission was 36.1% among 12 - &lt; 18-year-olds. The majority of ICU admits (91.8%) had no comorbidities.

Conclusion
Children too young to be vaccinated had the highest incidence of COVID-19 hospitalization, while adolescents had the highest proportion of ICU admissions. To prevent severe disease in children and adolescents, everyone eligible should be vaccinated.

Disclosures
Nicola P. Klein, MD, PhD, CSL Seqirus: Grant/Research Support|GlaxoSmithKline: Grant/Research Support|Merck: Grant/Research Support|Pfizer: Grant/Research Support|Sanofi Pasteur: Grant/Research Support
P-5. Human Papillomavirus Vaccination Coverage Among Girls and Boys in the United States: A Birth Year Cohort Analysis of the National Immunization Survey-Teen, 2016–2022
Authors: Meyer Sarah , Nmn Yankey David , Elam-Evans Laurie , Pingali Sandy , Stokley Shannon K , Singleton James A , Nyika Ponesai 
Published: January 2025

Abstract

Background
Human papillomavirus (HPV) causes approximately 37,000 cancers in the United States annually. HPV vaccine, recommended by CDC at age 11 or 12 years, prevents more than 90% of HPV-attributable cancers. We aim to identify coverage gaps to guide targeted interventions.

Methods
We conducted a birth cohort analysis among adolescents born 1999-2009 using National Immunization Survey-Teen (NIS-Teen), a random-digit dialed telephone survey which also collects vaccination data from providers. We analyzed 131,553 records from 2016 to 2022 NIS-Teen data to determine: 1) trends in coverage with ≥ 1 HPV vaccine dose before age 13 years (on-time initiation), 2) cumulative coverage from 13 to 17 years (catch-up), 3) on-time HPV vaccination up to date status (all recommended doses before age 13 years), 4) missed vaccination opportunities (provider visits before age 13 years where HPV unvaccinated adolescents received other recommended vaccine but not HPV vaccine), and achievable coverage if HPV vaccination opportunities were not missed. Regression analysis provided the average percentage increase in coverage across birth cohorts. Kaplan-Meier method provided cumulative HPV vaccination coverage from age 13 to 17 years, stratified by birth cohorts.

Results
HPV vaccination coverage before 13 years increased from 27.0% among adolescents born in 1999 to 69.8% among those born in 2009. Coverage for girls increased from 37.4% to 73.4%; coverage for boys increased from 16.9% to 65.9%. Overall, coverage increased from 33.1% before age 13 years to 74.9% before age 18 years. HPV vaccination up to date status increase from 10.3% among adolescents in 1999 to 42.2% among those born in 2009. Among the 38,568 (29.3%) who had not received any HPV vaccination, 31,513 (82.5%) had ≥ 1 missed HPV vaccination opportunity. The potential achievable vaccination coverage if opportunities were not missed was 94.8%.

Conclusion
Coverage with on-time HPV vaccination and HPV up to date increased by birth cohort among adolescents born 1999–2009 but remains suboptimal. Low uptake increases risk for HPV cancers. Opportunities for HPV vaccination before age 13 years are being missed and can be reduced by effective provider recommendations for HPV vaccination and by administering all recommended vaccines during the same visit.

Disclosures
All Authors: No reported disclosures
P-2007. Prognosis of COVID-19 Patients with Preexisting Dementia: Findings from a Comprehensive Multicenter Propensity-Matched Cohort Study in Brazil
Authors: Chagas Victor Schulthais , Ramos Lucas Emanuel F , Pires Magda Carvalho , da Silva Rosa Patryk Marques , Reis Gomes Virginia Mara , de Alvarenga Joice Coutinho , Meira Karina Cardoso , Romero Aliberti Márlon Juliano , Camargos Bicalho Maria Aparecida , Marcolino Milena S 
Published: January 2025

Abstract

Background
Despite the increasing knowledge about Covid-19 manifestations, there is still a lack of studies regarding the impact of the pandemic in patients with dementia. This study aims to evaluate clinical characteristics and outcomes of patients with dementia hospitalized due to Covid-19.

Methods
This retrospective observational study is part of a multicentric cohort that analyzed data from 38 hospitals from 19 Brazilian cities. Patients were included if they were ≥ 60 years old and hospitalized due to laboratory-confirmed Covid-19 between March 2020 and March 2022. Demographics data, clinical characteristics at admission, laboratory findings and outcomes were collected. Patients were matched in a propensity score analysis according to the presence or absence of dementia and stratified by age, sex, number of comorbidities, hospital, and year. A logistic regression model to estimate the propensity score was employed.

Results
Overall, 1,556 patients were included (median age 82 [interquartile range [IQR] 76-87 years], 58.7% women). A total of 405 had dementia diagnosed in medical records or by statement. Dementia group presented a higher prevalence of dyspnoea, cough, myalgia, headache, anosmia and ageusia compared to those without dementia. At hospital admission, dementia group had a higher prevalence of delirium (38.5% vs. 22.5%; p&lt; 0.001), fever (49.4% vs. 41.7%; p=0.009), sensory impairment (57.3% vs. 25.6%; p&lt; 0.001) and lower frequency of invasive mechanical ventilation support (23% vs. 37.8%; p&lt; 0.0001). Palliative care was more frequent in dementia patients when compared to controls (39.8% vs. 19.7%; p&lt; 0.001). There were no clinically relevant differences in laboratory results. Regarding outcomes, those with dementia had shorter length of stay in hospital (7.0 vs. 9.0 days; p=0.026), lower frequency of sepsis (17.0% vs. 24.0%; p=0.005) and kidney replacement therapy (6.4% vs. 9.8; p=0.002). There was no difference observed in hospital mortality between groups.

Conclusion
Clinical characteristics of Covid-19 differ between older patients with and without dementia. Dementia alone cannot explain the higher short-term mortality due to Covid-19. Other risk factors such as frailty and acute morbidity should be considered.

Disclosures
All Authors: No reported disclosures
P-2009. COVID-19 in Children with Hematological/Oncological Diagnoses – Exploring Reasons for Better Clinical Outcomes
Authors: Pinninti Swetha , Trieu Connie , Knoppova Barbora , Pati Sunil , Barley Avangelos , Latting Misty , Halima Sama , Ridings Alexis , Poulson Sydney , Whelan Kimberly , Bemrich-Stolz Christina , Britt William , Boppana Suresh 
Published: January 2025

Abstract

Background
The majority of COVID-19 infections in children, including in those with underlying hematological and oncological (Heme-Onc) diagnoses are mild with good outcome compared to adults. Postulated reasons include cross-protection from immunity against seasonal coronaviruses (HCoV’s), subdued inflammatory responses in children than in adults and differences in humoral and T-cell responses. The objectives of this study are to compare antibody responses against HCoV’s, anti-SARS-CoV-2 humoral, T-cell, and inflammatory profiles between Heme-Onc children with COVID-19 and control groups.

Methods
Binding IgG antibodies against Spike (S) of SARS-CoV-2, four HCoV’s (HKU1, OC43, NL63 and 229E), quantitative levels of 21 cytokines and 9 chemokines (multiplexed solid-phase electrochemiluminescence assay by Meso Scale Diagnostics/MSD) were compared among five cohorts: 1) children with Heme-Onc diagnoses and COVID-19 (n = 41) 2) healthy children with COVID-19 (n = 21) 3) adults with COVID-19 (n = 14) 4) children with multisystem inflammatory syndrome (MIS-C) [n = 23] and 5) healthy children without COVID-19 (n = 12). Additionally, T-cell responses against S and nucleocapsid (N) proteins of SARS-CoV-2 was assessed using ELISpot in Heme-Onc children a group of healthy children COVID-19.

Results
Anti-S antibodies and neutralizing antibodies against SARS-CoV-2 and HCoV were significantly lower in children in Heme-Onc and healthy children with COVID-19 compared to adults with COVID-19 (Figure 1). The concentration of eight pro-inflammatory cytokines and chemokines were significantly lower in Heme-Onc and healthy children compared to adults with COVID-19 and children with MIS-C. The responder T-cell frequency varied between 0 and 860/100,000 PBMC at study enrollment in children with Heme-Onc diagnoses.

Conclusion
In this single-center study, cross-protection from HCoV antibodies is an unlikely mechanism to explain mild COVID-19 in children, including in those with underlying hematological and oncological diagnoses. Subdued inflammatory responses to SARS-CoV-2 could be one of the factors for the mild COVID-19 disease phenotype in children.

Disclosures
Swetha Pinninti, MD, Moderna: Grant/Research Support|Pfizer: Grant/Research Support Suresh Boppana, MD, GSK: Advisor/Consultant|Merck: Grant/Research Support|Pfizer: Grant/Research Support
P-2056. Modelling the Relative Vaccine Effectiveness of ARCT-154 versus BNT162b2 using Immunogenicity Data
Authors: Nguyen Van , Crepey Pascal , Pivette Jean Marie , Settembre Ettan , Rajaran Sankarasubramanian , Youhanna John , Ferraro Aimee , Chang Cheng , Van Boxmeer Josephine , Mould-Quevedo Joaquin F 
Published: January 2025

Abstract

Background
Vaccination has become an essential weapon in the global battle against COVID-19. While showing high effectiveness against the original Wuhan-Hu-1 strain and early SARS-CoV-2 variants, questions have surfaced regarding the duration of immunity they provide, especially with the emergence of new viral strains. The innovative self-amplifying (SA)mRNA vaccine, ARCT-154, has demonstrated clinical improvements in extending duration of immune response. Our objective was to compare the long-term efficacy of ARCT-154 with BNT162b2 in an adult population by assessing relative vaccine effectiveness (rVE) over time.

Methods
rVE was estimated using a two-step approach. First, we used geometric mean titer data (Days 29, 91, and 181 post-vaccination) from a phase 3 double-blind controlled clinical trial comparing the immune response of ARCT-154 and BNT162b2 against Wuhan-Hu-1 and Omicron BA.4/5 in healthy 18–77-year-olds (Japan Registry for Clinical Trials identifier: jRCT2071220080). We then incorporated this information into a published model correlating immunogenicity and efficacy to calculate the rVE of ARCT-154 versus BNT162b2 in symptomatic and severe cases.

Results
ARCT-154 exhibited an increasing rVE against symptomatic infection with Wuhan-Hu-1 over time, ranging from 2.11% on Day 29 to 8.51% on Day 181 post-vaccination. rVE against symptomatic Omicron infection was 0% on Day 29 but increased to 13.85% by Day 91 and 20.25% by Day 181. rVE against severe illness ranging from 1% to 4% for Wuhan-Hu-1 and 1% to 13% for Omicron across all measured time points.

Conclusion
ARCT-154 showed longer-lasting protection than BNT162b2 against symptomatic and severe COVID-19 for both the original Wuhan-Hu-1 and Omicron BA.4/BA.5 strains.

Disclosures
Van Nguyen, PhD, CSL Seqirus USA: Advisor/Consultant Pascal Crepey, n/a, CSL Seqirus USA: Advisor/Consultant Jean Marie Pivette, n/a, CSL Seqirus USA: Advisor/Consultant Ettan Settembre, n/a, CSL Seqirus USA: Stocks/Bonds (Private Company) Sankarasubramanian Rajaran, n/a, CSL Seqirus UK: Stocks/Bonds (Private Company) John Youhanna, n/a, CSL Seqirus USA: Stocks/Bonds (Private Company) Aimee Ferraro, n/a, CSL Seqirus USA: Stocks/Bonds (Private Company) Cheng Chang, n/a, CSL Seqirus USA: Stocks/Bonds (Private Company) Josephine Van Boxmeer, n/a, CSL Seqirus Amsterdam: Stocks/Bonds (Private Company) Joaquin F. Mould-Quevedo, PhD, CSL Seqirus USA: Stocks/Bonds (Private Company)