bluuebunny/crossref_metadata_2025_split huggingface dataset:
P-1916. The impact of SARS-CoV-2 VOCs on clinical outcomes: an Umbrella Review
Authors: Fama Federico , Fattore Rebecca , Raimondo Paolo , Brivio Fabio , Holmes Darcy , Muheberimana Toussaint , Nayfeh Tarek , Gori Andrea , Passerini Matteo , Colaneri Marta 
Published: January 2025

Abstract

Background
Studies aiming to synthetize data from literature are helpful to valid the robustness of associations, to assess the quality of the data, and, eventually, to propose recommendations. This is particularly evident for the huge amount of data reported for SARS-CoV-2.
The aim of this study was to perform an umbrella review to identify the strength and validity of associations between variants of concern (VOCs) and pre-specified clinical outcomes in COVID-19 patients.
Table 1
Effect size measures reported in the studies included in the review, divided by outcome.
Acronyms: CI, confidence interval; OR: odds ratio; RR, risk ratio; cCFR, confirmed case-fatality risk; HFR, hospitalization-fatality risk; N/A, not available

Methods
An umbrella review according to the principles to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was performed searching multiple databases in January 2024. Peer reviewed systematic reviews considering ≥ 2 VOCs with a clinical outcome among death, hospitalization, severe disease, admission to intensive care unit (ICU), and mechanical ventilation were included. Data on study population and measures of association between clinical outcome and VOCs were considered. The quality of the studies was assessed through the AMSTAR-2 tool. The effect size measures with the confidence interval for each association between VOCs and clinical outcomes were reported. Subgroup analyses were performed, if possible. A citation matrix was used to assess the overlap between the systematic reviews included.
Table 2
Risk of bias assessment of the included systematic reviews using the AMSTAR-2 score. In bold the key domains.

Results
A total of 11 studies were included in our review. 24 total comparison were considered, most regarding Omicron versus Delta (19/24), where Omicron was always associated with better clinical outcomes than Delta. The overall quality of the studies was low. None of the reviewed studies incorporated consideration of risk factors other than VOCs in evaluating clinical outcomes.
The overlap between the included reviews is low, only 10% of them having a significant overlap ( &gt; 15%).

Conclusion
Our umbrella review shows the lower hazard on human health of the Omicron compared to Delta variant. However, the quality of the reviews included were generally low and there is a lack of correction with other risk factors such as comorbidities and vaccination status.
While our review provides valuable insights into the association between VOCs and clinical outcomes of SARS-CoV-2 infection, further research incorporating risk factor analysis and ensuring methodological rigor is warranted.

Disclosures
All Authors: No reported disclosures
P-1918. Incidence of viral rebound in hospitalized COVID-19 patients
Authors: Weng Tzu-Ping , Syue Lingshan , Li Mingchi , Lee Nan-Yao 
Published: January 2025

Abstract

Background
Viral rebound, characterized by a resurgence of viral activity after initial suppression, presents a potential threat to infection control within healthcare settings. We aimed to investigate the incidence of viral rebound in patients hospitalized for COVID-19.

Methods
The retrospective study included symptomatic adults admitted for COVID-19 to a tertiary hospital in Taiwan during 1 January 2022 to 31 December 2022. Viral rebound was defined as an increase of △Ct ≥ 5 units or a new positive test after having tested negative during 10-30 days after COVID-19 diagnosis. The indication of antiviral agent was evaluated by physician according to initial severity and risks to develop severe COVID-19. The patients with prior COVID-19 infections, receipt of ≥ 2 antiviral agents, incomplete treatment course of antiviral agent, or active problem for hospitalization other than COVID-19 were excluded.

Results
Of the included 354 participants, 26 received Paxlovid, 98 received molnupiravir, 54 received 3-day remdesivir, 101 received 5-day remdesivir, and 84 didn’t receive any antiviral agent. The incidence of viral rebound was higher in patients not receiving antiviral agent (n=75) compared to those who received either antiviral therapy (n=279) (17.3% vs. 11.5%, p=0.18). Additionally, the duration from COVID-19 diagnosis to onset of viral rebound was similar between the two groups (16.2 days vs. 14.3 days, p=0.20). Among the 148 with severe COVID-19, viral rebound was higher in patients without antiviral agent exposure (n=47) compared to those who received 5-day remdesivir (n=101) (21.3% vs. 15.8%, p=0.18). In 206 with non-severe disease, no significant differences were found in the incidence of viral rebound between patients who received Paxlovid (n=26) and molnupiravir (n=98) (11.5% vs. 7.1%, p=0.44).

Conclusion
Our study highlights the risk of viral rebound in hospitalized COVID-19 patients. Patients without antiviral treatment had a higher rebound incidence. Among severe cases, antiviral therapy reduced rebound rates, underscoring its importance. Interestingly, antiviral choice did not significantly affect rebound incidences in non-severe cases. These findings stress the crucial role of antiviral therapy in infection control strategies.

Disclosures
All Authors: No reported disclosures
P-1940. Low Visceral Fat Volume and Hypoalbuminemia as Prognostic Markers in Hospitalized Patients with COVID-19 During the Omicron Variant Epidemic
Authors: Nakayama Shin , Wakabayashi Yoshitaka , Kawase Kyotaro , Yamamoto Ai , Kitazawa Takatoshi 
Published: January 2025

Abstract

Background
The rate of severe cases of coronavirus disease 2019 (COVID-19) has decreased since the Omicron variant became epidemic. Visceral fat volume was a risk factor for COVID-19 severity with prior prevalent variants, but whether visceral fat volume remains a risk factor for the Omicron variant is unclear. We investigated the associations of clinical factors including visceral fat volume with severity and mortality among hospitalized patients with COVID-19 during the Omicron variant epidemic.Table 1.Multivariable analysis of clinical factors associated with COVID-19 severity.

Methods
We included hospitalized patients with COVID-19 during the Omicron variant epidemic who underwent computed tomography of the abdomen. Clinical data were obtained from the medical records and visceral fat area (VFA) was measured using a 3-dimensional image analysis system volume analyzer. Severity was determined by the presence or absence of oxygen supplementation.Table 2.Multivariable analysis of clinical factors associated with mortality in hospitalized 206 patients with COVID-19.

Results
Among the 226 patients, 66 patients showed moderate severity and 29 patients were non-survivors. Hypoalbuminemia was associated with severity (odds ratio [OR] 3.93, 95% confidence interval [CI] 1.91–8.07; p=0.0002)(Table 1), and hypoalbuminemia (OR 8.38, 95%CI 2.37–29.58; p=0.0010) and low VFA (OR 3.40, 95%CI 1.15–10.06; p=0.027) were associated with mortality (Table 2). Decision tree analysis showed that mortality rate in the hypoalbuminemia and low-VFA group (37.3%) was significantly higher than in other groups (p&lt; 0.01)(Fig.1).Fig 1.Decision tree analysis of patient mortality rates classified by serum albumin level and visceral fat area.Patients were initially classified with a cutoff value of 3.5 g/dL for serum albumin, then classified into four groups using a cutoff value of 100 cm² for visceral fat area.

Conclusion
Low visceral fat volume and hypoalbuminemia were associated with mortality in hospitalized patients with COVID-19 during the Omicron variant epidemic. Classification by VFA and serum albumin may allow simple prediction of mortality risk among hospitalized patients with COVID-19.

Disclosures
All Authors: No reported disclosures
P-1941. COVID-19 Impact on Acute Pancreatitis Hospitalization and Mortality: A Retrospective United States Cohort Study
Authors: Suenghataiphorn Thanathip , Lohawatcharagul Tuntanut , Wattanachayakul Phuuwadith , Kulthamrongsri Narathorn , Danpanichkul Pojsakorn , Polpichai Natchaya , Thongpiya Jerapas 
Published: January 2025

Abstract

Background
Acute pancreatitis, a prevalent gastrointestinal condition, frequently necessitates hospitalization and is associated with potential adverse in-hospital outcomes. Recent data showed the detrimental effects of COVID-19 infection on acute pancreatitis, particularly in patients with severe COVID-19 infections. However, limited information exists on the specific impacts of COVID-19 infection in patients hospitalized for acute pancreatitis.

Methods
We analyzed the 2020 U.S. National Inpatient Sample (NIS) to investigate the effects of COVID-19 infection on cases primarily admitted due to acute pancreatitis. Participants aged 18 and above were identified using relevant ICD-10 CM codes. Adjusted odds ratios (aORs) for specified outcomes were calculated through multivariable logistic and linear regression analyses. The primary outcome was inpatient mortality, with secondary outcomes including system-based complications. Statistical significance was established at a P value of 0.05.

Results
We identified 252,435 patients with a primary discharge diagnosis of acute pancreatitis. The mean age was 50.1 years; 48.6% were female. Caucasians accounted for 41%, followed by Hispanics. Of these, 1.05% (2,675/252,435) had a concurrent diagnosis of COVID-19 infection.
In a survey multivariable logistic and linear regression model adjusting for patient and hospital factors, COVID-19 infection was associated with higher in-hospital mortality (aOR 3.71; 95% CI 2.01, 6.84, P &lt; 0.001), prolonged length of stay (β LOS 1.05; 95% CI 0.46, 1.64, P &lt; 0.001), increased hospitalization charge ( β charge 9,327; 95% CI 820, 17834, P &lt; 0.001), and acute respiratory failure (aOR 2.49; 95% CI 1.75, 3.53, P &lt; 0.001), We observed non-significant, but increased, risks of shock, acute kidney injury (AKI), pancreatic pseudocyst, acute respiratory distress syndrome (ARDS), and mechanical ventilation in COVID-19 positive patients.

Conclusion
In conclusion, our study underscores that COVID-19 infection is associated with higher in-hospital mortality, prolonged hospital stays, and increased incidence of acute respiratory failure in patients diagnosed with acute pancreatitis. Future longitudinal studies are warranted to comprehensively assess the long-term health sequelae in this population.

Disclosures
All Authors: No reported disclosures
P-1. Impacts of a Quality Improvement Initiative to Build Confidence in Human Papillomavirus (HPV) Vaccination Among American Indian Communities
Authors: Humiston Sharon G , Molloy Leah , Simone Laura , Napolitan Chris , Carter Jeffrey D , Meza Jimenez Jenniffer A , Anderson Chadha Chelsie , Douglas Bonnie 
Published: January 2025

Abstract

Background
HPV vaccination is highly effective to prevent HPV-associated cancers, but uptake among adolescents and young adults remains suboptimal. This program aimed to identify barriers and support HPV vaccine confidence in American Indian communities in partnership with a Rural Tribal Clinic in Nevada and an urban Federally Qualified Health Center (FQHC) in North Dakota.

Methods
Clinics led 3 live education sessions virtually or in-person from 3/23 to 8/23, which were attended by 91 patients and family members (patients) and 10 healthcare professionals (HCPs). Surveys were administered before, immediately after, and 3 months after each session.

Results
At baseline, 70% of HCPs reported facing hesitancy from patients about the HPV vaccine, with top challenges including patient refusal to discuss vaccination (43%) and sexual stigma around HPV (29%). When asked to identify their patients’ top reason for not getting the HPV vaccine, HCPs reported low perception of self-risk (40%). Conversely, patients reported their top concerns were long-term (39%) and short-term (32%) side effects. When asked what they thought would increase patient interest in vaccination, HCPs identified a strong recommendation from their doctor (60%) while patients prioritized learning more about HPV and associated cancers (57%). Patient HPV vaccine knowledge and confidence improved after sessions. More patients recognized that the HPV vaccine can prevent certain cancers (92% vs 60%, p &lt; .001) and agreed the vaccine is safe (95% vs 64%, p &lt; .001) after sessions than before. Awareness of vaccine access also improved: more patients recognized that vaccines are available free of charge after sessions than before (95% vs 66%, p &lt; .001). Most patients (90%) reported being likely to share what they learned with family and friends, and 100% of providers were likely to lead another session. At 3-month follow-up, HCPs had helped a total of 75 patients get the HPV vaccine.

Conclusion
This initiative highlights the feasibility and impact of clinic-based education sessions on patient vaccine knowledge and confidence and offers insights into community-level barriers and motivators to vaccination.

Disclosures
Sharon G. Humiston, MD, MPH, Sanofi: Advisor/Consultant|Sanofi: Honoraria
P-1993. Nirmatrelvir/Ritonavir in Immunocompromised Hosts: Use and Outcomes from a Cancer Center
Authors: Drucker Darra , Kassamali-Escobar Zahra , Tverdek Frank , Liu Catherine , Rosen Emily A 
Published: January 2025

Abstract

Background
Prolonged viral replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in immunocompromised (IC) hosts has raised questions about whether treatment duration with nirmatrelvir/ritonavir (nirmatrelvir/r) should be longer than the authorized 5-day course. Data describing nirmatrelvir/r treatment outcomes are limited in the IC population. The primary objective of this study was to assess the efficacy of a nirmatrelvir/r 5-day course as treatment for coronavirus disease 2019 (COVID-19) in IC patients.

Methods
A retrospective chart review was conducted at Fred Hutchinson Cancer Center (FHCC) of patients ≥ 18 years old with an active hematologic malignancy who received nirmatrelvir/r under Emergency Use Authorization between 12/22/21 - 5/25/23. Patients with an active oncology treatment plan within 3 months (before or after) their nirmatrelvir/r prescription date were included. Patients who received nirmatrelvir/r under Investigational New Drug authorization were excluded. The primary outcome was a composite of all-cause mortality or COVID-19 related hospitalization within 30 days of nirmatrelvir/r. A secondary outcome, persistent COVID-19 infection, was defined as a positive SARS-CoV-2 polymerase chain reaction test 30-90 days after initial positive test.

Results
Among 928 patients who received nirmatrelvir/r at FHCC, 399 patients were included. Median age was 63 years, 55% of patients were male, and lymphoma was the most common malignancy, 48% (Table 1). Thirty-day all-cause mortality or COVID-19 related hospitalization occurred in 39/399 (9.8%) of patients. Thirteen patients (3.3%) had persistent COVID-19 infection; 8 had persistent symptoms and 5 required additional treatment. Early discontinuation of nirmatrelvir/r due to adverse effects, most commonly gastrointestinal, occurred in 11 (2.8%) patients (Table 2).

Conclusion
Incidence of the primary outcome was higher in our population compared to rates in nirmatrelvir/r phase 3 trial data and driven by hospitalization rather than all-cause mortality. Persistent infection requiring further treatment occurred in only 1.3% of patients. Additional studies are needed to define optimal treatment duration, including potential indications for use &gt; 5 days in IC hosts.

Disclosures
Frank Tverdek, PharmD, Merck: Advisor/Consultant Catherine Liu, MD, Pfizer: Grant/Research Support
P-1997. Real-world Effectiveness of Tixagevimab/cilgavimab for COVID-19 Pre-exposure Prophylaxis in Solid Organ Transplant Recipients during the BA.2.75 and BQ.1 Omicron Variant Period: A matched Case-control Dtudy
Authors: Rojanakit Gun , Kiertiburanakul Sasisopin , Boongird Sarinya , Sutharattanapong Napan , Kantachuvesiri Surasak , Yingchoncharoen Teerapat , Sobhonslidsuk Abhasnee , Bruminhent Jackrapong 
Published: January 2025

Abstract

Background
Solid organ transplant recipients (SOTRs) develop poor immunogenicity after SARS-CoV-2 immunization. The neutralizing monoclonal antibody combination of tixagevimab/cilgavimab (T/C) has been shown to reduce the risk of COVID-19 among this vulnerable population. We assessed the effectiveness and safety of T/C pre-exposure prophylaxis (PrEP) for COVID-19 protection after transplantation.

Methods
We conducted a matched case-control study at a single transplant center during the Omicron lineages BA.2.75 and BQ.1 period (August 2022 to February 2023). T/C doses of 150/150 mg were provided from August 2022 until February 2023, and doses of 300/300 mg were administered thereafter (December 2022 to February 2023). All patients were followed for up to 6 months, and adverse events (AEs) from T/C were assessed.

Results
A total of 143 SOTRs were included, with 115 and 28 SOTRs in the T/C and control groups, respectively. Transplants included kidney (n=108), liver (n=28), and heart (n=9). Over 6 months, 18 (15.7%) in T/C developed COVID-19, with onset at median 3 months. All had mild infections without respiratory failure. Mild and reversible adverse events (AEs) were reported in 25.2% of cases. No rejection occurred. Non-significantly lower COVID-19 within 3 months during BA.2.75 Omicron (8.7% vs. 17.9% in control; p=0.128; effectiveness: 51.4%). At 6 months (BQ.1 Omicron), COVID-19 incidence was 15.7% in T/C vs. 17.9% in control (p=0.667; effectiveness: 12.3%). The occurrence of COVID-19 was not significantly different after adjustment for the number of vaccine doses, history of prior COVID-19, or the dose of T/C.

Conclusion
The effectiveness of T/C tends to be protective against susceptible strains, although the severity of breakthrough infections tends to be mild. Short-term safety as PrEP appears tolerable. TCTR20220801004.

Disclosures
All Authors: No reported disclosures
P-7. A study of influenza vaccination response in disabled stroke patients
Authors: Pakngao Achiraya , Suwatcharangoon Sureerat , Ngamjanyaporn Pintip , Boonnak Kobporn , Suangtamai Tanitta , Rotjanapan Porpon 
Published: January 2025

Abstract

Background
To date, no clinical study has confirmed the clinical efficacy of routine annual vaccination in stroke patients. The primary objective was to study the immunologic response to influenza vaccination between functional-dependence (FD) and functional-independence (FI) ischemic stroke patients.
Median hemagglutination titers at T0 and T1

Methods
A prospective observational study was conducted between 2023 and 2024 at Ramathibodi Hospital. Old ischemic stroke patients were screened for eligibility. Enrolled patients received standard doses of inactivated trivalent influenza vaccine. Data on patient demographics were retrieved. Blood samples were collected for hemagglutination inhibition (HAI) before and 4-8 weeks after vaccination to determine seroprotection and seroconversion rates.

Results
As per the interim analysis, 198 patients were enrolled, and 161 individuals have completed the HAI analysis. The mean ages (±SD) of the control (C), FI, and FD groups were 69.4±7.4 years, 71.4±8.6, and 75.9±8.3, respectively (p&lt; 0.001). The FD group had significantly higher baseline IFN-α2, IFN-γ, IL-6, IL-12p, and IL-18 levels than the FI and C groups.
Before (T0) and after (T1) vaccination, the proportion of participants with HAI titers &gt;1:40 on the A/Sydney (H1N1) strain in the FI group was significantly higher than in the FD group (p=0.031 and 0.003 at T0 and T1, respectively) similarly to the A/Darwin (H3/N2) and the B/Austria strains and individuals achieved titer &gt;1:160 (p=0.046 at T1). The C group displayed the highest seroconversion rates compared to the FI and the FD groups at 34.2%, 25.4%, and 19.4% (p=0.033). There were three probable and 23 possible influenza infections three months after enrollment. Twenty-two of 198 patients developed mild adverse events associated with influenza vaccination.

Conclusion
The FI group achieved higher seroprotection and seroconversion rates than the FD group. The possible associated factors were higher levels of pro-inflammatory cytokines at baseline, resulting in better vaccination responses in the FI group. Therefore, the FD group may require a different influenza vaccination strategy to achieve more appropriate immune responses.

Disclosures
All Authors: No reported disclosures
P-2054. Effectiveness of a Single COVID-19 mRNA Vaccine Dose in Individuals Previously Infected with SARS-CoV-2: A Systematic Review
Authors: Volkman Hannah R , Nguyen Jennifer L , Mustapha Mustapha M , Yang Jingyan , Jodar Luis , McLaughlin John M 
Published: January 2025

Abstract

Background
Based on the high levels of population immunity to SARS-CoV-2 from prior infection in many countries, in fall 2023 the US Food and Drug Administration, European Medicines Agency, and World Health Organization authorized/recommended a single mRNA XBB.1.5-adapted vaccine dose for unvaccinated individuals aged ≥ 5y.

Methods
This systematic literature review evaluated the vaccine effectiveness (VE) of a single COVID-19 mRNA dose (BNT162b2 or mRNA-1273) in individuals previously infected with SARS-CoV-2 compared to those with differing histories of prior infection and vaccination (PROSPERO ID: CRD42023453257). We searched MEDLINE and Embase for VE studies published from January 1, 2021–October 4, 2023. Data were synthesized following Synthesis Without Meta-Analysis guidelines. Bias was assessed using the Newcastle-Ottawa Scale. VE estimates were reported as a range of point estimates per clinical endpoint and meta-analyses were not performed due to heterogeneity.

Results
Of 1,661 initial results, 18 studies were eligible for inclusion. Among those previously infected, a single mRNA dose (compared to being unvaccinated) increased protection by 8–71% against infection (related to Omicron BA.1, BA.4/5, or XBB), 39–67% against symptomatic infection (BA.1, BA.2, or BA.4/5), and 25–60% against hospitalization or hospitalization or death (BA.1). The protection provided by a single dose among those previously infected was comparable to the VE provided by two doses, and was higher than VE following two doses without prior infection. No studies were identified that reported single-dose VE for adapted vaccines (BA.1 or BA.4/5 bivalent or XBB.1.5-adapted formulations), immunocompromised populations, or children aged &lt; 5y.

Conclusion
Our results suggest that a single dose of COVID-19 vaccine provides similar protection to that conferred by a two-dose series for immunocompetent individuals aged ≥ 5y in the current setting of high pre-existing SARS-CoV-2 immunity. These findings support current recommendations for one dose of COVID-19 vaccines regardless of vaccination status to be given in advance of the viral respiratory season with considerations for additional doses for certain special populations including young children, older adults, and the immunocompromised.

Disclosures
Hannah R. Volkman, PhD, MPH, Pfizer Inc: Employment|Pfizer Inc: Stocks/Bonds (Public Company) Jennifer L Nguyen, ScD, MPH, Pfizer Inc: Employment|Pfizer Inc: Stocks/Bonds (Public Company) Mustapha M. Mustapha, MD, PhD, MPH, Pfizer Inc: Employment|Pfizer Inc: Stocks/Bonds (Public Company) Jingyan Yang, MHS, DrPH, Pfizer Inc: Employment|Pfizer Inc: Stocks/Bonds (Public Company) Luis Jodar, PhD, Pfizer Inc: Employment|Pfizer Inc: Stocks/Bonds (Public Company) John M. McLaughlin, PhD, Pfizer: Employee|Pfizer: Stocks/Bonds (Public Company)