bluuebunny/crossref_metadata_2025 huggingface dataset:
P-2042. Development and Maintenance of a Pharmacist-Run COVID-19 Outpatient Treatment Clinic at a Veterans Affairs Hospital
Authors: Gllava Sidorela , Ward Tiffany , Kim Sung Soo , Vega Vivian
Published: January 2025

Background

In December 2021, oral nirmatrelvir/ritonavir and molnupiravir were approved under Emergency Use Authorization for the treatment of COVID-19 in high-risk outpatients. At that time, National Institutes of Health also recommended intravenous (IV) remdesivir and monoclonal antibodies. The Infectious Diseases team at our hospital designed a protocol for a multidisciplinary Outpatient Clinic that would offer oral and IV therapy to high-risk patients. This protocol used an elaborate scoring guide to identify and prioritize patients based on degree of immune compromise, age, comorbid conditions, and vaccination status.

This clinic made it possible for numerous patients to have access to potentially life-saving therapies. This joint initiative and multidisciplinary effort is, to our knowledge, the first ever Covid Outpatient Clinic, functional 7 days a week/365 days a year.

Methods

Per protocol, if a patient tested positive for COVID-19 and deemed high-risk, a provider would place a consult for outpatient therapy. A pharmacist would then review for the appropriate medication based on symptom onset, renal/hepatic function, and drug-drug interactions (DDI). If a patient was not a candidate for oral therapy, they would be scheduled for an IV infusion. Patients were counseled on adverse effects, DDI mitigation, etc. All consults were completed within 24 hours.

Results

Since January 2022, over 2000 consults were reviewed and 1767 approved for therapy. A total of 1476 patients were treated with oral agents and 291 patients with an IV infusion. Each consult took approximately 45 minutes for pharmacy review and ∼3 hours of nursing time for an infusion. A sub-analysis of 450 nirmatrelvir/ritonavir patients revealed that 65 required a dose adjustment based on renal function and 369 patients required at least one adjustment to concomitant medications due to DDIs.

Conclusion

After two years and despite many logistical challenges, we have been able to successfully sustain an Outpatient clinic that provides IV and oral therapy to our veterans, any day of the year. Through this pioneer effort, we have created many foundational interprofessional relationships and we believe this clinic can serve as a model for future endeavors to improve patient care.

Disclosures

All Authors: No reported disclosures
P-2043. Outpatient Antiviral Treatment Among High-risk Patients with Mild to Moderate COVID-19 During the Omicron Surge
Authors: Syue Lingshan , Lee Nanyao , Ko Wen-Chien
Published: January 2025

Background

In response to the COVID-19 pandemic, outpatient treatment with oral antiviral medications has emerged as a crucial strategy to manage the disease effectively. This study aimed to evaluate the clinical outcomes of such treatment modalities in a cohort of confirmed COVID-19 patients.

Methods

This is a retrospective study of COVID-19 cases with high risk diagnosed during an Omicron wave from May 2022 to December 2022 in Taiwan. Cases received either nirmatrelvir-ritonavir (NMV/r) or molnupiravir (MOV) as outpatient treatment were enrolled to assess the clinical effects of therapeutic strategies. The 30-day crude mortality and hospitalization were the primary endpoint.

Results

Among 2932 patients with prescriptions of antiviral agents, 1395 patients received NMV/r, and 1537 received MOV. The average age of the patients was 63.8 years, with a majority (59%) being over 65 years old. Common comorbidities included diabetes (24.7%), chronic kidney disease (20.7%), cardiovascular diseases (17.6%), and a history of cancer (15.6%). The overall hospitalization rate was 15%, with a mortality rate of 0.7% which revealed promising clinical outcomes with outpatient treatment using either NMV/r or MOV. Compared with NMV/r, those on MOV were older (59.6 ± 18 years vs 67.4 ± 15 years, p< 0.001) and the proportion of cardiovascular disease (8.7% vs 19.5%) and chronic kidney disease (4.1% vs 28.5%) were higher. COVID-related 30-day hospitalization rate and mortality were higher in the MOV group significantly (15.5% vs 8.5%, p < 0.001; 0.8% vs 0.4%, p< 0.0001).

Conclusion

Outpatient treatment with NMV/r and MOV demonstrated effectiveness in reducing hospitalization and mortality rates among COVID-19 patients. Therefore, selecting outpatient treatment with these antiviral medications could represent an effective strategy for managing COVID-19, contributing to improved patient outcomes and reduced hospitalization needs.

Disclosures

All Authors: No reported disclosures
P-2055. Modelling the Relative Vaccine Effectiveness of ARCT-154 versus BNT162b2 in Younger and Older Adults
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

Background

While vaccines have proved a key tool in protection from COVID-19, the duration of immunity induced by first-generation mRNA vaccines is limited. Self-amplifying mRNA (SA-mRNA) vaccines have clinically shown to both elicit higher antibody responses and increase the duration of response. In this analysis, we evaluate the relative vaccine effectiveness (rVE) over time of a COVID-19 SA-mRNA vaccine (ARCT-154) versus BNT162b2 against the original Wuhan-Hu-1 and Omicron BA.4/BA.5 strains in adults stratified by age group (< 60 years and ≥60 years), using a correlate of protection derived from immunogenicity data.

Methods

We used geometric mean titer data collected on Days 29, 91, and 181 post-vaccination from a phase 3 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) to estimate a correlate of protection against symptomatic and severe COVID-19. rVE of ARCT-154 versus BNT162b2 was then evaluated for each time point against both endpoints in individuals < 60 years and ≥60 years of age.

Results

rVE against symptomatic infection and severe illness increased over time against both Wuhan-Hu-1 and Omicron BA.4/BA.5. In adults < 60 years, rVE against symptomatic infection ranged from 2.57% on Day 29 to 9.19% on Day 181 against Wuhan-Hu-1 and from 4.24% to 26.83% against Omicron BA.4/5. In adults ≥60 years, rVE ranged from 2.77% to 10.99% and 4.58% to 48.02% against the two strains, respectively. rVE against severe illness ranged from 0.30% to 4.65% against Wuhan-Hu-1 and 0.63% to 15.84% against Omicron BA.4/5 in adults < 60 years and from 0.34% to 5.61% and 0.74% to 27.96%, respectively, in adults ≥60 years.

Conclusion

ARCT-154 showed longer-lasting protection than BNT162b2 against symptomatic and severe COVID-19, with greatest benefits in adults ≥60 years of age against Omicron BA.4/BA.5.

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)
P-2059. Perceptions and Factors Associated with Uptake of Monovalent XBB.1.5 BNT162b2 COVID-19 Vaccine among Healthcare Workers in Peru
Authors: Gonzales-Zamora Jose A , Araoz-Salinas Julieta M , Quispe-Vicuña Carlos , Reátegui García Martín Ernesto , Ortiz-Saavedra Brando , Soriano-Moreno Anderson N , Baltazar-Ñahui Hans , Alave Jorge
Published: January 2025

Background

The implementation of the XBB.1.5 BNT162b2 COVID-19 vaccine (updated vaccine) occurred in Peru in January 2024, since then, many questions about its efficacy and safety have been raised. Addressing these concerns is crucial, especially among healthcare workers, given their high risk of acquiring COVID-19 and their role in promoting vaccination. This study investigated the factors and perceptions associated with healthcare workers’ uptake of the updated vaccine.Figure 1:Perceptions about the updated monovalent vaccine among healthcare workers in Peru

Methods

We conducted a cross-sectional study based on an online survey from March 21 to May 1, 2024. Healthcare workers (physicians, nurses, etc.) living and practicing in Peru were included. We calculated crude prevalence ratios with 95% confidence intervals to determine the associated factors and perceptions using Poisson regression with robust variance.Table 1:Factors associated with uptake of the updated monovalent vaccine among healthcare workers (Page 1)

Results

We included 393 healthcare workers, predominantly female (55.2%) and physicians (63.9%), almost half aged 30-49 years (50.9%). The majority (72.8%) reported not being vaccinated with the updated vaccine, but 65% of them intended to do it. Regarding perceptions, more than 70% of respondents thought the updated vaccine was necessary and protective against severe COVID-19 and mortality, but only 16.5% believed it caused severe adverse events. Only 24.7% felt the Peruvian Ministry of Health was informing well about the vaccines (Figure 1). In the bivariate analysis, the uptake of this vaccine was significantly higher among those who had a history of COVID-19 (p = 0.005), had received the bivalent vaccine (p< 0.001), or more than five vaccine doses (p< 0.001), and among those who felt the vaccine should be recommended (p=0.015) or even mandatory for high-risk people (p=0.04). On the other hand, the uptake was lower in those who thought the vaccine was not necessary (p=0.043) or did not protect against mortality (p=0.037) (Table 1).Table 1:Factors associated with uptake of the updated monovalent vaccine among healthcare workers (Page 2)

Conclusion

History of COVID-19, receiving multiple vaccine doses, and recommending the updated vaccine for high-risk people are factors associated with vaccine uptake. There are still major concerns about the government's communication regarding vaccination. These findings underscore the importance of targeted interventions and communication strategies to improve the poor vaccination rate among healthcare workers in Peru.Table 1:Factors associated with uptake of the updated monovalent vaccine among healthcare workers (Page 3)

Disclosures

All Authors: No reported disclosures
P-2061. Long-term Follow Up of Pfizer-BioNTech BNT162b2 mRNA Vaccinations Reveals Persistent Disparities between SARS-CoV-2 Naive and Infected Individuals in the Context of Breakthrough Infections
Authors: Marklund Emelie , Lundgren Anna , Bemark Mats , Nyström Kristina , Li Ying , Yilmaz Aylin , Andersson Lars-Magnus , Gisslen Magnus
Published: January 2025

Background

Previous studies have reported that differences in IgG and T cell responses between SARS-CoV-2 naïve and previously infected patients diminish after two vaccine doses. Yet, long-term data beyond one year and after three vaccinations is limited, with the lack of information on the impact of breakthrough infections.

Methods

108 health care workers (HCWs) from a Swedish Infectious Diseases University Clinic were included. IgG antibodies against the receptor-binding domain (RBD) and nucleocapsid (N) were measured along with cytokine-induced T cell responses (IFN-γ, IL-2, TNF-α) using an in-house assay. Samples were collected before (PreDX) and one month after (PDX) each dose of the mRNA Pfizer-BioNTech COVID-19 vaccine, from January 2021 until December 2022. Eligible HCWs underwent PCR-testing when showing SARS-CoV-2 associated symptoms. Breakthrough infection was identified by a positive PCR/antigen test or as in the N-IgG seroconversion post-vaccinations. Mean concentrations were compared between groups after adjustment for age and sex, using mixed model.

Results

In total, 34 HCWs (32%) were infected prior to vaccinations. Breakthrough infections were initially few, but increased rapidly from December 2021, with 77% of the HCWs discovered with a breakthrough infection one year later (Tabel 1, Fig 1).

Infected HCWs, including those previously SARS-CoV-2 naïve with breakthrough infections, consistently had higher RBD-IgG concentrations than uninfected, except from PD3 (Figure 2). Significant differences in IFN-γ were noted at all time points except PD3 and PD4. Significant differences in IL-2 was only observed within the first month, and in TNF-α at PreD4 (Figure 2).

Those with breakthrough infections had significant higher RBD-IgG concentrations at all measured time points (PD3-PD4), with a similar pattern in IFN- γ, except from PD4.

Conclusion

Differences in cellular and humoral immune responses to SARS-CoV-2 between infected and naïve individuals remain significant up to 23 months post-vaccination, when considering breakthrough infections.

Disclosures

All Authors: No reported disclosures
P-2064. COVID-19 Vaccination-infection Status and Immunological Profile: Identification of High-Risk Population for Targeted Booster Immunization In India
Authors: Mittal Ankit , Gujjarlapudi Deepika , Gajapathi Raju Vidyavathi devi , Veturi Sadhana Yelamanchili , Talukdar Rupjyoti , Banerjee Rupa , Jagtap Nitin , Krishnaiah Sannapaneni , Veeraiah Namburu , Reddy Duvvur Nageshwar
Published: January 2025

Background

The immunological profiles and predictors of immune response in people with hybrid immunity, resulting from a combination of natural infection and vaccination, particularly in regions where non-mRNA vaccines were administered, remain less understood.

Methods

This was a cross-sectional study done at AIG Hospitals, Hyderabad, India. Consecutive participants were enrolled, and sampled for immunological testing. The study population was divided into six cohorts based on their infection and vaccination status. Immunological assays were performed to measure anti-spike protein and interferon-γ release assay. Hospitalization rates were compared in all groups. Chi-square test was used to compare categorical variables, and the Mann-Whitney U test was used for comparing medians. Post-hoc Dunn test was used for pairwise comparison. Bonferroni adjustment for p-value was performed for multiple pairwise comparisons. Linear regression model was used appropriately to find predictors of antibody titres.

Results

A total of 1040 patients were enrolled in the study. The population was divided into six cohorts: Unvaccinated, Primary, Booster, Hybrid (Pre-Omicron only), Hybrid (Omicron only), and Hybrid (Both). Antibody titres and IGRA levels were found to be statistically higher in the Hybrid (both infection) group (Table 1 and Figures 1a & 1b). The linear regression model showed factors predicting antibody response (Table 2). Age and hypertension were independent (negative) predictors of antibody levels.

During the follow-up (median 30.7 [26.6 – 34.4 months]) of 1008 patients, 770 (76.4%) had a documented COVID infection with Omicron. Hospitalization was evaluated in three groups: Hybrid, vaccination only and unvaccinated. The incidence was significantly lower in the Hybrid group; log-rank test: p < 0.001. (Figure 2)

Conclusion

The prevalence of hybrid immunity was high in the study population. Individuals above 60 years old and with comorbidities are more likely to have lower antibody titers. Immunized patients were protected against hospitalization. There is a need for prioritized immune-boosting efforts in high-risk individuals.

Disclosures

All Authors: No reported disclosures
P-2103. Non-invasive Group A Streptococcus Infection in the United States, 2012 – 2023: a National Reference Laboratory Retrospective Study
Authors: Lee Min Kyung , Engler Howard , Stainback Rita , Alfego David , Naccache Samia
Published: January 2025

Background

Non-invasive Group A Streptococcus (GAS) infection prevalence is not actively monitored, however understanding seasonal patterns can help inform unexpected trends in invasive and non-invasive GAS prevalence.

Methods

De-identified results from 23,601,754 specimens for GAS detection from throat swabs performed at Labcorp sites from January 2012 – December 2023 were included in a retrospective, cross-sectional cohort study. 2,605,482 specimens with diagnostic tests to detect bacteria including GAS from blood culture positive bottles were included as a surrogate for invasive GAS infection (iGAS). Cross-correlation tests were used to compare the time series patterns for URT GAS and GAS bacteremia. Age-adjusted prevalence ratios comparing GAS prevalence in 2023 to 2017 were calculated using metabin function in the meta R package. Multivariable logistic regression models were used to test for association between patient sex, age, and geographic location and GAS infection.

Results

The highest URT GAS infection levels occurred between the 8th to 16th weeks of the year. Higher Risk of URT GAS infection was confirmed in patients 6 – 11 years of age and 15% increased risk was observed in males. Higher positivity of non-invasive Group A Streptococcus infection was consistently observed in East North Central, Middle Atlantic and Pacific divisions of the United States. A large decrease in non-invasive Group A Streptococcus infection due to the COVID-19 pandemic was followed by a significant resurgence in late 2022 and early 2023, with return to seasonal patterns in late 2023. Prevalence of URT GAS infections in March 2023 was 55% greater than the prevalence of URT GAS infections in March 2017 (age-adjusted PR: 1.55, 95% CI: 1.52 – 1.58). iGAS positivity rates generally corresponded to URT GAS positivity rates during the same time period, including during GAS resurgence in late 2022 and early 2023.

Conclusion

Data from national reference lab outpatient testing can provide potentially statistically significant infectious disease surveillance trends.

Disclosures

Min Kyung Lee, PhD, Labcorp: Salary Howard Engler, PhD, D(ABMM), Labcorp: Salary|Labcorp: Stocks/Bonds (Public Company) Rita Stainback, MS, MT (ASCP) SM, DLM, Labcorp: Salary David Alfego, PhD, Labcorp: Employee|Labcorp: Stocks/Bonds (Public Company) Samia Naccache, PhD, D(ABMM), Labcorp: Salary|Labcorp: Stocks/Bonds (Public Company)
P-2123. Unveiling Mortality Patterns in Candidemia: Insights from a Multi-Species Analysis from a Global Research Network
Authors: Thompson George R , Alhayek Soubhi , Chastain Daniel B , Ferraz Carolina , Salinas Jorge , Sillau Stefan , Henao Martínez Andrés F
Published: January 2025

Background

Candidemia remains a critical concern in healthcare settings due to its high mortality rates and increasing prevalence of multidrug-resistant strains. Understanding the impact of different Candida species on patient outcomes is crucial for effective management and treatment strategies. This study aims to comprehensively analyze the association between Candida species and mortality in candidemia cases.

Percentages of 1-year mortality by Candida species.

Methods

We queried TriNetX, a global research network database (https://trinetx.com/), to identify patients with positive candidemia in blood by PCR testing from 2020-2023. We captured mortality as the primary outcome at one year in patients with candidemia categorized by Candida species. The time to death within the one year period was assessed using Kaplan-Meier plots, along with the non-parametric log-rank and Peto-Peto tests. Additionally, Cox proportional hazards (PH) models, both unadjusted and adjusted for demographic and comorbidity covariates, were employed for comparative analysis.

Unadjusted Kaplan-Mier Survival analysis with failure estimates in candidemia by Candida species

Results

We captured 1,233 candidemia episodes during the study period. The distribution of Candida species was C. albicans (498, 40.4%), C. glabrata (333, 27%), C. auris (151, 12%), C. parapsilosis (121, 9.8%), C. tropicalis (59, 5%), C. krusei (28, 2%), and poly-candidemia (44, 4%) (Table 1). The one-year mortality varied across species, ranging from 15.3% to 36.6% (Figure 1). The unadjusted Kaplan-Mier Survival analysis showed that poly-candidemia, followed by C. tropicalis, had a worse survival than C. auris, which had the lowest risk (Figure 2). Adjusted Cox PH model found C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and poly-candidemia had statistically significantly higher mortality rates than C. auris. Additionally, age, non-Hispanic ethnicity, residence in the Western US region, and a higher Charlson comorbidity index value emerged as independent predictors of increased mortality (Table 2).

Clinical features by Candida species

Conclusion

Among patients with candidemia, we found an overall 1-year mortality of 28%. The associated resistance of C. auris may translate into a decreased virulence and a survival advantage. Additionally, older age and a higher comorbidity burden were associated with 1-year mortality.

Disclosures

George R. Thompson, III, MD, Astellas: Advisor/Consultant|Cidara: Advisor/Consultant|Cidara: Grant/Research Support|F2G: Advisor/Consultant|F2G: Grant/Research Support|Melinta: Advisor/Consultant|Melinta: Grant/Research Support|Mundipharma: Advisor/Consultant|Mundipharma: Grant/Research Support|Pfizer: Advisor/Consultant
P-2151. Interactive Dashboard for Tracking Malaria across the Veterans Health Administration (VA), 2000 – 2023
Authors: Epstein Lauren , Paredes-Vincent Ariana , Ogston Christopher , Rodriguez-Barradas Maria C , Bonomo Robert A , Brown Sheldon T , Woods Christopher
Published: January 2025

Background

The VA utilizes a comprehensive data system that is updated in real time and can be used to track trends and geographic shifts in emerging diseases across the U.S. Using malaria as an example, our goal was to illustrate the (1) feasibility of creating a dashboard to conduct public health surveillance using VA data, (2) assess trends, and (3) compare the VA and national trends using publicly available data.

Figure 1: Incidence of malaria across the VA System by location of diagnosis (inpatient vs. outpatient), 2000 – 2023.

Rate per 100,000 VA patients.

Methods

This project was developed as part of VA SHIELD, a comprehensive biorepository of specimens and clinical data that started in 2020 to address national health threats across the VA system. Within this overarching objective, we assessed trends in malaria cases across all VA facilities from 2000 – 2023 using the VA’s Corporate Data Warehouse.

We identified unique cases using 13 ICD-9 and 13 ICD-10 codes for malaria. We calculated incidence rates (per 100,000 population) based on all patients that received care at any type of VA facility (inpatient, outpatient). We compared the yearly VA rates with national rates using publicly available data in CDC’s WONDER database.

Figure 2: Comparison of malaria trends, VA vs. national surveillance (2000 – 2023)

VA rates includes both inpatient and outpatient locations combined.

Results

We identified 6,415 cases of malaria, ranging between 141 (2021) and 387 (2018) annually. The annual rate of malaria varied between 2.11 (2021) and 7.38 (2001) cases per 100,000 VA patients. The annual rate of malaria diagnosed among hospitalized patients ranged between 0.18 (2016) and 0.64 (2002) cases per 100,000 VA patients. In comparison, CDC reported national malaria rates varied between 0.18 (2020) and 0.65 (2023) per 100,000 persons. In 2020, there was a decrease in malaria rates that was observed both nationally and among the VA population.

Conclusion

Using the diagnosis of malaria, we show how the VA’s vast data system can contribute to public health surveillance. Historically, locally acquired malaria infections in the U.S. are rare. However, in 2023, 10 locally acquired cases of malaria were reported from 3 states, illustrating the possibility for wider transmission. This project illustrates the potential of the VA to detect rare infections in real time and possibly serve as a national sentinel surveillance platform. Future endeavors include prospective surveillance with specimen and clinical data collection in order to augment malaria public health surveillance.

Disclosures

All Authors: No reported disclosures
P-2153. Babesia Coinfection is not Associated with Higher Mortality in the United States, 2015-2023: a Retrospective Cohort Study
Authors: Ssentongo Paddy , Venugopal Natasha , Ba Djibril
Published: January 2025

Background

Babesiosis is a tickborne illness caused by the Apicomplexan parasites known as Babesia spp, and severe disease is associated with a high mortality rate. Babesiosis is often co-transmitted by other deer-associated zoonoses, including Lyme disease, Ehrlichiosis, and Anaplasmosis maintained by the same vector tick, Ixodes spp. These zoonoses are endemic in the Northeastern United States. Babesiosis-associated coinfection and mortality outcomes are not fully elucidated. The objective of the present study is determining babesiosis coinfection prevalence rates and estimate mortality outcomes.

Methods

TriNetX database between 2015 and 2023 was queried for patients with Babesiosis. Cox-proportional hazard model was employed to estimate the mortality risk associated with coinfections (Babesiosis infection co-diagnosed with one or more tickborne illnesses). The analysis focused on Babesiosis coinfection with Lyme disease, Ehrlichiosis, and Anaplasmosis. The exposure was coinfection, and the control group was the Babesia-only population. The primary outcome was a 90-day mortality from the diagnosis of Babesia.

Results

Of the 3521 Babesiosis patients, the mean age was 55 years (SD:18), 51% were male, 75% were White, 2% had asplenia, and 11% had malignancies. Babesiosis cases are on the rise with highest incidence in summer (Fig 1). The prevalence rate of 1 or more co-infection was 42%; 95% CI (40%-43%, Fig 2). Coinfection with Borrelia burgdorferi was the highest with 41%; 95% CI (39%-42%), followed by Ehrlichiosis at 3.7%; 95% CI (3.1%-4.4%). Overall, 90-day mortality was 1.4%; 95% CI (1.0%-1.8%). After adjusting for potential confounders, compared to the coinfections group, the mortality risk was lower in the Babesiosis-only group (HR: 0.43; (95% CI: 0.20-0.90, Fig 3).

Conclusion

In the extensive study of over 3000 patients with Babesiosis in the United States, the prevalence rates of coinfection were highest with Borrelia burgdorferi, followed by Ehrlichiosis. Rates for Anaplasmosis were low. Coinfection with other tick-borne infections did not increase mortality. It is plausible the findings are due to the likelihood of earlier detection and treatment of coinfection (particularly Lyme disease) with doxycycline.

Disclosures

All Authors: No reported disclosures
P-2155. Early Diagnosis of Dengue, Malaria, Scrub Typhus, Leptospira Using CBC and LFT Parameters in a Tertiary Care Hospital - A 10-year retrospective study
Authors: Kumar Suresh , Shibi S , Sanjai R , Shobana S
Published: January 2025

Background

Dengue, malaria and scrub typhus/leptospirosis are significant infectious diseases prevalent in tropical and subtropical regions. Timely and accurate diagnosis of these diseases is crucial for initiating appropriate treatment and preventing complications. Dengue shows increased Hb, AST should be greater than ALT, as well as a decrease in platelets, along with lymphocytes in the differential count should be observed. Scrub typhus/leptospirosis reveal dropping platelets, along with an increase in total count, alkaline phosphate, and GGTP should be observed. Malaria indicates reduced Hb and platelets, along with an increase in total bilirubin, alkaline phosphate, and GGTP should be noted. Additionally, monocytes and lymphocytes should be seen in the differential count.

Methods

This retrospective study conducted between January 2014-March 2024 at a tertiary hospital in India. We systematically reviewed the medical records of these patients, focusing on demographical, CBC and LFT parameters. Data were entered into an Excel spreadsheet, and descriptive statistics were employed for data interpretation.

Results

During the study period, a total of 99,431 were admitted. For Dengue 80.93% CBC and LFT were followed. In Scrub Typhus/Leptospirosis 58.6% were followed and in malaria 62.5% followed the CBC and LFT as shown in Table 1. Table 1:Cumulative summary of Dengue, Malaria, Scrub Typhus/LeptospiraCATEGORYFREQUENCY (N)PERCENTAGE (%)Total number of patients admitted99,431100%Total number of Dengue test done12,02012.08%NS-1 Ag Positive1,72614.35%CBC and LFT matched1,39780.93%Not matched32919.06%Total number of Scrub Typhus/Leptospirosis done2,8252.84%Positive IgM ELISA1505.30%CBC and LFT matched8858.6%Not matched6241.3%Total number of Malaria test done7,8807.92%Positive MP by QBC320.40%CBC and LFT matched2062.5%Not matched1237.5%

Conclusion

This study highlights the significant burden of Dengue, Scrub Typhus/Leptospirosis, and Malaria in a tertiary care setting in India. While Dengue was the most prevalent, all three diseases demonstrated the potential for early diagnosis by utilizing both CBC and LFT parameters.

Disclosures

All Authors: No reported disclosures
P-2166. Sensitivity and Specificity of Nanopore Sequencing for Detection of Methicillin-Resistant Staphylococcus aureus and Methicillin-Resistant Staphylococcus epidermidis in Positive Blood Culture Samples
Authors: Mangkalamanee Onjira , Kawang Kornthara , Cholsaktrakool Pornsawan , Maita Supakorn , Prasertmanakit Tongsorn , Pollapong Kraiwit , Srichomthong Chalurmpon , Shotelersuk Vorasuk , Punakabutra Napawan , Chatsuwan Tanittha , Nilaratanakul Voraphoj
Published: January 2025

Background

Nanopore sequencing enables rapid DNA/RNA analysis without amplification. Implementing this for point-of-care diagnostics reduces time delays in traditional AST methods, potentially enhancing patient outcomes. We aim to evaluate the performance of Oxford Nanopore Technologies sequencing from positive blood culture for bacterial identification and antimicrobial susceptibility prediction in S. aureus and S. epidermidis by detecting the mecA gene.

Methods

We conducted a cross-sectional descriptive study on individuals with positive blood cultures identifying S. aureus and S. epidermidis over a 12-month period from April 2023 to March 2024. Bacterial DNA was extracted from the blood culture specimens, and then sequenced using the PromethION Flow Cell to identify the organisms and mecA genes, comparing the results to routine blood cultures and standard AST.

Results

108 blood culture samples were initially collected. After applying the exclusion criteria, 80 samples qualified for DNA extraction and sequencing. 45 samples were identified as S. aureus (6 MRSA and 39 MSSA) and 35 as S. epidermidis (27 MRSE and 8 MSSE). Notably, 67.5% of samples contained less than 0.5 ng/μl of DNA. Sensitivity and specificity of mecA gene detection were 35.5% (95% CI: 18.6%–52.3%) and 83.7% (95% CI: 73.3%–94.0%), respectively, with an accuracy of 65.0% (95% CI: 54.5%–75.5%). Upon excluding samples with DNA less than 0.5 ng/μl accuracy improved to 73.1% (95% CI: 56.0%–90.1%). The specimen that showed a false-positive result will proceed to phenotypic confirmation using methicillin-infused mannitol-salt agar. After phenotypic confirmation, the accuracy improved to of 88.5% (95% CI: 76.2%–100.0%). In this study, we also found 5 samples in which the mecA gene was shown to be genotypically oxacillin-sensitive after phenotypic confirmation. The median time for detecting the mecA gene was 198 minutes (IQR: 37.5–458.7) after the onset of sequencing.

Conclusion

Our study on nanopore sequencing for MRSA and MRSE detection from blood cultures found promising but limited sensitivity and specificity in detecting mecA gene. Challenges in DNA extraction from Gram-positive bacteria affected overall accuracy. Further improvements are needed for enhanced diagnostic reliability.

Disclosures

All Authors: No reported disclosures
P-2167. "Clinical Utility of Cell-free Next-generation Sequencing, Single Center Experience"
Authors: Ibrahim Osama , Rogers Ralph , Farmakiotis Dimitrios
Published: January 2025

Background

Timely diagnosis of infectious diseases is crucial, but it can be challenging. The literature about impact of Karius in clinical care is still insufficient. Overall, Karius has been very effective on selected patients but the clinical impact is difficult to assess due to absence of gold standard comparator. In addition, a negative result doesn’t always mean a “true negative” but means that the organism’s DNA wasn’t detected. Also, Identification of non-relevant results has been reported.

Methods

This is a retrospective cohort study of patients who received a Karius testing between January 2018 until March 2023 at Lifespan institution in Rhode Island. Clinical and demographic data was abstracted from the electronic medical record. Quality checks were applied to the data to remove duplicates and errors. Descriptive statistics were reported using Microsoft excel. Clinical impact was abritrated after review of each case by three independent investigators. We predefined clinical impact categories criteria based on criteria from previous studies. Each case was reviewed by each investigator independently and disparities were solved via consensus and discussions. inter-rater reliability was assessed using Cohen's Kappa coefficient.

Results

Overall, 65 patient had Karius testing and included 35 male and 30 female. 30 patients were immunocompromised and 16 of them had hematologic malignancy. Mean age was 46.7 and the study included 12 pediatric and 53 adult patient. The most common infectious syndrome was Pneumonia/pulmonary followed by osteoarticular and endovascular. Management was changed in 11/65 patients. The Karius testing had positive impact in 12 patients, negative impact in 1 patient and no impact in 52 patients. Positive percent agreement with conventional testing was 0.49 and negative percent agreement was 0.83

Conclusion

Cell-free next-generation sequencing has a valuable role in diagnosis and management of infections in challenging cases especially in patients with high pretest probability. Further research is needed to define the population who would benefit most from it.

Disclosures

All Authors: No reported disclosures
P-2181. Cardiac MRI Identifies Heart Disease Risk in Individuals with Hepatitis C Regardless of Myocardial Damage Markers or Fibrosis Stage
Authors: D’Amore Aaron , Sirajuddin Arlene , George Nivya , Gharib Ahmed M , Mathur Poonam
Published: January 2025

Background

Infection with hepatitis C virus (HCV) increases the risk of extrahepatic manifestations, including cardiovascular disease (CVD). Cardiac magnetic resonance (CMR) remains the gold standard test for non-invasive structural and functional assessment of the heart and can be used to detect CVD. We sought to determine the CVD risk in patients with HCV prior to therapy using CMR.Table 1.Baseline Demographic Features of HCV CMR Cohort

Methods

Individuals with chronic HCV infection were prospectively enrolled in the CHROME study (NCT 03823911). A subset of 10 HCV-infected individuals were enrolled in the MRI sub-study from March to September 2019. HCV antibody and RNA, liver fibrosis score, and markers of inflammation and myocardial damage were obtained.

CMR was performed prior to the initiation of DAA treatment. ECV fraction was calculated using the equation: ECV = 100% x (1-hematocrit) x [(1/T1myocardium post) – (1/T1myocardium pre)]/[(1/T1blood post) – (1/T1 blood pre)]. An ECV fraction > 30% was considered abnormally increased. 10 age-matched, HCV-negative volunteers were included in the analysis so that T-test was used to compare ECV fraction in both groups.Figure 1.Extracellular Volume (ECV) of HCV-infected individuals and Healthy Volunteers. ECV fraction in the HCV-infected individuals was significantly increased (0.30 ±0.03 vs. 0.26±0.03, p=0.0036).

Results

Demographics are shown in Table 1. CMR showed that 8 of 10 HCV-infected individuals had an abnormal ECV fraction ( >30%)7 (average=0.30, range 29-38%). When compared with age-matched normal volunteers, ECV fraction in the HCV-infected individuals was significantly increased (0.30 ±0.03 vs. 0.26±0.03, p=0.0036) (Figure 1). Three of 10 HCV-infected individuals had non-ischemic patterns of gadolinium enhancement on the LGE images (Figure 2). For HCV-infected individuals, markers of inflammation and myocardial damage were within laboratory reference range for all subjects in the CMR cohort, and ECV fraction was elevated regardless of myocardial damage markers or liver fibrosis stage.Figure 2.A) Short axis late gadolinium enhancement image shows a midwall pattern of enhancement within the basal septal wall (arrow), compatible with an area of midwall fibrosis. B) Native T1 map and C) post contrast T1 map show a corresponding area of abnormal T1 measurements within the basal septum (arrows).

Conclusion

Our findings suggest that myocardial changes secondary to HCV infection can occur without measurable changes in inflammatory or myocardial biomarkers, and ECV fraction via CMR may be a sensitive screening tool to detect these changes. This has important implications for the necessity of early HCV treatment, since cardiovascular changes can precede the development of advanced liver fibrosis in HCV-infected individuals.

Disclosures

All Authors: No reported disclosures
P-2182. Assessing Hepatitis A Virus (HAV) and Hepatitis B Virus (HBV) Screening, Immunity, and Vaccination in People Living with Human Immunodeficiency Virus (HIV) in the Illinois Department of Corrections (IDOC)
Authors: Truong Nicholas T , Dang Alex , Debs Hillary , Morrow Jennifer , Kalota Huda , Patel Mahesh C , Borgetti Scott , Drwiega Emily N , Badowski Melissa E
Published: January 2025

Background

Individuals in custody are highly susceptible to vaccine-preventable diseases, including hepatitis A virus (HAV) and hepatitis B virus (HBV). In the Illinois Department of Corrections (IDOC) HIV Telemedicine Clinic, people are screened for HAV/HBV, providing an opportunity to recommend vaccines in those without immunity.

Methods

This retrospective cohort pre-post study included adults living with HIV who followed in the IDOC HIV Telemedicine Clinic during two time periods, 01/01/2019 - 12/31/2019 and 01/01/2022 – 12/31/2022, with a 9-month follow-up period to account for screening and vaccination recommendations. Patients were excluded from primary endpoint analysis if they had chronic HBV infection. The primary objective was to compare the rates of vaccination and immunity to HAV and/or HBV among individuals in custody living with HIV in 2022 to prior data in 2019, where standardized recommendations for serologic screening and vaccination were not routinely performed. Secondary endpoints included the number of individuals receiving HAV/HBV screening, acceptance of vaccination if recommended, and documented barriers to vaccination. Statistical analysis included descriptive statistics, Chi-squared test, and Student’s t-test.

Results

A total of 436 patients were included in the 2019 cohort and served as historical control data. Of 341 patients screened for inclusion in the 2022 cohort, 300 were included. Baseline characteristics are presented in Table 1. 79% and 70% of patients were immune to HAV in 2019 and 2022, respectively (p = 0.02). 65% and 71% of patients were immune to HBV in 2019 and 2022, respectively (p = 0.12). Overall, the number of patients immune to both HAV and HBV were similar between the two cohorts with 52% in 2019 and 53% in 2022 (p = 0.89). On the other hand, the percentage of patients who had no immunity to both HAV and HBV was 8% in 2019 and 12% in 2022 (p = 0.08). Patient refusal was the main barrier to vaccination. Other secondary outcomes for 2022 are outlined in Table 2.

Conclusion

Overall, HAV and HBV immunity did not significantly increase in 2022. Results suggest that a major opportunity still exists to screen and provide vaccination to individuals in custody, but routine serologic screening can lead to improved HAV and HBV immunity rates.

Disclosures

Scott Borgetti, MD, GSK: Grant/Research Support
P-2259. Incidence, Treatment, and Outcomes of Urinary Tract Infections Caused by Extended-Spectrum Beta-Lactamase Producing Bacteria in Kidney Transplant Recipients
Authors: Gerdes Elise N , Wynd Michael A , Chaung Melissa
Published: January 2025

Background

Urinary tract infections (UTI) are the most common bacterial infection in kidney transplant recipients (KTR) during the first year post transplant. The objective of this study was to determine the incidence of UTI caused by extended-spectrum beta-lactamase (ESBL) producing bacteria in KTR and compare their outcomes to KTR with UTI caused by non-ESBL producing pathogens.

Index Urinary Tract Infections (2013-2022)

Methods

This was a single-center, retrospective, chart review including adults who received their first, kidney-alone transplant from January 2013 through December 2022 and had a UTI within the first year post-transplant. A UTI was defined as a positive urine culture treated with antibiotics and presence of ESBL-producing bacteria was confirmed by susceptibility patterns. Patients were excluded if they had a rejection or received augmented immunosuppression prior to index UTI, received treatment for positive donor cultures, or were dialysis-dependent at 90 days post-transplant. Primary outcomes: incidence of index UTI caused by ESBL producing bacteria, location of treatment, and length of stay. Key secondary outcomes: patient and allograft survival, incidence of biopsy-proven rejection after treatment of index UTI, and number of UTI in the first year post-transplant.

Primary Outcome: Hospitalizations

Results

Of 178 patients included, 21 (11.8%) had a UTI due to ESBL-producing bacteria and 157 (88.2%) had a UTI caused by a non-ESBL producing organism. The incidence of ESBL-UTIs increased from 0 to 18.5% during the observation period. No differences were identified in baseline characteristics except for receipt of a donation-after-cardiac-death kidney, 8 (38.1%) in the ESBL-UTI group and 28 (17.8%) in the non-ESBL UTI group, p = 0.03. Compared to the non-ESBL-UTI group, the ESBL-UTI group was more likely to be admitted for treatment 11/21 (52.2%) vs 40/157 (25.5%), p = 0.01, and had more UTIs in the first post-transplant year, mean (range) 2.7 (1-6) vs 1.8 (1-7), p = 0.003. No differences were identified in other outcomes.

Empiric Therapy in Patients with Extended-Spectrum β-lactamase Urinary Tract Infections

Conclusion

The incidence of index UTI due to ESBL-producing bacteria is increasing while the UTI rate remains consistent, creating the need to identify optimal treatment and prevention strategies in KTR.

Secondary Outcome: Total Urinary Tract Infections in the First Year Post-Transplant

Disclosures

All Authors: No reported disclosures
P-2281. Impact of Immunosuppression on Clinical Outcomes in Critically Ill Pneumonia Patients
Authors: Sanabria-Herrera Natalia , Torres Antoni , Martin-Loeches Ignacio , Reyes Luis Felipe F
Published: January 2025

Background

Nosocomial lower respiratory infections (nLRTI) are linked to poorer clinical outcomes and a significant healthcare cost. Nevertheless, there remains uncertainty regarding the risk factors for mortality among critically ill individuals, particularly those with varying degrees of immunosuppression. Thus, this study aims to comprehensively describe immunocompromised patients, assess its impact on clinical outcomes, and conduct a comparative survival analysis.

Figure 1

Identified microorganisms in A) the Immunosuppression group and B) Non- the Immunosuppression group

Methods

This analysis used data from the prospective, multicenter, and multinational cohort developed by the European Network for ICU-related respiratory infections (ENIRRI), including 1060 adult patients diagnosed with nLRTI. Descriptive statistics were utilized to compare the immunosuppressed group against the non-immunosuppressed group, while also detailing the microorganisms predominantly identified in both groups. A survival analysis adjusted for infection severity using a Cox proportional hazards model was performed to explore mortality within these subgroups further.

Figure 2

Kaplan-Meier survival curve stratified by Immunosuppression status: Probability of survival from ICU admission

Results

Immunosuppression was observed in 25% of the patients (264/1060). In both cohorts, Pseudomonas aeruginosa was the predominant microorganism, particularly affecting immunosuppressed patients, (25.3% vs. 16.7%, p = 0.032), followed by Klebsiella spp and Acinetobacter baumanii (Figure 1). Interestingly, the survival analysis revealed a lower probability of survival in the non-immunosuppressed after admission to the ICU (Figure 2). Additionally, the Cox regression analysis adjusted by disease severity found that no-immunosuppressed patients had lower mortality.

Figure 3

Adjusted Kaplan-Meier Survival Curve following Cox Regression: Survival Probability Adjusted for SAPS II Score.

Conclusion

This description sheds light on the intricate relationship between immunosuppression, microbial etiology, and clinical outcomes in patients with nLRTI. Interestingly, immunosuppression was not associated with worse clinical outcomes, even after adjusting for disease severity.

Disclosures

All Authors: No reported disclosures
P-2302. Efficacy of Universal vs Targeted Antifungal Prophylaxis for the Prevention of Invasive Fungal Infections after Lung Transplant
Authors: Claire Ashmead-Meers , Miceli Marisa H , Linder Kathleen A , Kauffman Carol A , Richards Blair
Published: January 2025

Background

IFI are associated with high morbidity and mortality among LTx patients (pt). Preventive strategies are commonly used, but the optimal AP approach is unclear. Over the last 10 years, our LTx program has transitioned from universal AP with itraconazole (ITR), to targeted AP, and now universal AP with posaconazole (POS). We compared the efficacy of these strategies.

Methods

All adult LTx pt at U Michigan from 7/1/2014-2/28/2023 were followed for 12 months (mo) post-LTx. Pt were divided into 3 cohorts based on AP regimen: cohort 1 - universal ITR for 6 mo; cohort 2 - targeted voriconazole (VOR) for 3 mo if colonized with Aspergillus or fluconazole (FLU) for 14 days (d) if colonized with Candida; cohort 3 - universal POS for 6 mo. Demographics, LTx characteristics, IFI defined by MSGERC criteria, breakthrough IFI (B-IFI) defined by MSGERC/ECMM criteria, and mortality were noted.

Results

Of 134 pt, 86 (64%) were men, and 101 (75%) had double-LTx. Pulmonary fibrosis was the most common reason for LTx (47,35%). There were 59 (44%), 29 (22%), and 46 (34%) pt in the universal ITR, universal POS, and targeted cohorts, respectively. A total of 23 proven/probable IFI occurred: 14 invasive pulmonary aspergillosis (IPA), 7 invasive candidiasis (IC), 1 cryptococcal pneumonia (CP) and 1 hyaline mold IFI. IFI occurred at a median of 98 d (range 1–322 d). IFI occurred in 6/59 (10%) receiving universal ITR (all but one of whom had IPA, all B-IFI); 5/29 (17%) receiving universal POS (3 IC and 2 IPA, all B-IFI); and 12/46 (26%) in the targeted AP cohort (7 IPA, 4 IC, 1 CP). Of the 12 pt with IFI in the targeted cohort, 10 did not meet criteria for use of AP and thus were not given VOR or FLU; 7/10 developed IPA and 2/10 IC. No IPA occurred in 5 pt who received VOR AP, but 2 pt on FLU AP developed breakthrough IC. Kaplan-Meier curve showed a trend toward IFI-free survival at 12 mo to be greater among pt receiving universal ITR (0.89) and universal POS (0.83) vs. targeted AP (0.73), p=0.16. All-cause mortality was 10% (14/134) and did not differ among the 3 AP cohorts, p=.49. Only 1 death (IC) was caused by IFI.

Conclusion

Universal AP using POS or ITR may be a more effective strategy than targeted AP for prevention of IFI post-LTx, but this comes with an increased risk for harder-to-treat B-IFI.

Disclosures

Marisa H. Miceli, MD, AN2: PI in clinical trial|F2G: PI in clinical trial|Pulmocide: PI in clinical trial|Scynexis: Advisor/Consultant|Scynexis: PI in clinical trial