bluuebunny/crossref_metadata_2025_split huggingface dataset:
364. Individualized Prognostics in COVID-19 Facilitated by Computer Recognition of Blood Leukocyte Subsets
Authors: Libertin Claudia R , Kempaiah Prakash , Durvasula Ravindra , Rivas Ariel 
Published: December 2021

Abstract

Background
To determine whether CBC differentials of COVID+ inpatients can predict, at admission, both maximum oxygen requirements (MOR) and 30-day mortality.

Methods
Based on an approved IRB protocol, CBC differentials from the first 3 days of hospitalization of 12 SARS CoV-2 infected patients were retrospectively extracted from hospital records and analyzed with a privately owned Pattern Recognition Software (PRS, US Patent 10,429,389 B2) previously validated in sepsis, HIV, and hantavirus infections. PRS partitions the data into subsets immunologically dissimilar from one another, although internally similar.

Results
Regardless of the angle considered, the classic analysis −which measured the percentages of lymphocytes, monocytes, and neutrophils− did not distinguish outcomes (A). In contrast, non-overlapping patterns generated by the PRS differentiated 3 (left, vertical, and right) groups of patients (B). One subset was only composed of survivors (B). The remaining subsets included the highest oxygenation requirements (B). At least two immunologically interpretable, multi-cellular indicators distinguished the 3 data subsets with statistically significant differences (C, p≤ 0.05). Survivors (the left subset) showed lower N/L and/or higher M/L ratios than non-survivors (the vertical subset, C).Therefore, PRS partitioned the data into subsets that displayed both biological and significant differences. Because it offers visually explicit information, clinicians do not require a specialized training to interpret PRS-generated results.
CBCs vs. outcomes - Software-analyzed CBCs vs. outcomes

Conclusion
(1) Analysis of blood leukocyte data predicts MOR and 30-d mortality. (2) Real time PRS analysis facilitates personalized medical decisions. (3) PRS measures two dimensions rarely assessed: multi-cellularity and dynamics. (4) Even with very small datasets, PRS may achieve statistical significance. (5) Larger COVID+ infected cohort is being analyzed for potential commercialization.

Disclosures
Claudia R. Libertin, MD, Gilead (Grant/Research Support)
366. Abbott BinaxNOW Rapid Antigen Test Performance in Detecting SARS-CoV-2 Infections in a COVID-19 Outbreak Among Horse Racetrack Workers
Authors: Surasi Krishna , Cummings Kristin J , Hanson Carl V , Morris Mary Kate , Salas Maria , Seftel David , Ortiz Liza M , Thilakaratne Ruwan , Stainken Cameron , Wadford Debra 
Published: December 2021

Abstract

Background
Rapid antigen tests (e.g., Abbott’s BinaxNOW) are cheaper and faster than nucleic acid amplification tests (e.g., real-time reverse transcription polymerase chain reaction [RT-PCR]) for SARS-CoV-2 infection, with variable reported sensitivity. A horse racetrack in California experienced a COVID-19 outbreak among staff and used BinaxNOW to supplement RT-PCR. Utility of BinaxNOW in detecting SARS-CoV-2 infection in a workplace outbreak was assessed.

Methods
Between November 25–December 22, 2020, anterior nasal swabs were collected from racetrack staff for six rounds of paired BinaxNOW and RT-PCR tests. BinaxNOW tests were interpreted according to manufacturer instructions. RT-PCR was performed at the state public health lab using the ThermoFisher TaqPath COVID-19 Combo Kit. Staff with positive results on either test were isolated and removed from subsequent testing. Viral cultures were attempted on specimens with cycle threshold (Ct) &lt; 30.

Results
Overall, 769 paired results from 342 staff were analyzed. Most were of Hispanic ethnicity (62.0%) and ages ranged from 18 to 92 years (median 52). BinaxNOW performance compared to RT-PCR (95% CI) was as follows: positive percent agreement (PPA) 43.3% (34.6%–52.4%); negative percent agreement (NPA) 100% (99.4%–100%); positive predictive value (PPV) 100% (93.5%–100%); negative predictive value 89.9% (87.5%–92.0%). Among 127 RT-PCR-positive specimens, those with paired BinaxNOW-positive results (n = 55) had a lower mean Ct value than those with paired BinaxNOW-negative results (n = 72) (17.8 vs. 28.5) (p &lt; 0.001). In dual positive pairs, median time from specimen collected to RT-PCR result reported was 4 days (range 1-6), compared to the 15-minute BinaxNOW reporting time. Of 100 Ct &lt; 30 specimens, 51 resulted in positive virus isolation, 45 (88.2%) of which were BinaxNOW-positive.

Conclusion
High NPA and PPV support immediate isolation of BinaxNOW-positive individuals, while low PPA supports confirmatory testing following BinaxNOW-negative results. BinaxNOW performed better in paired specimens with lower Ct value and positive viral cultures, which could suggest that among RT-PCR-positive specimens, those that are BinaxNOW-negative may be less likely to contain infectious virus than those that are BinaxNOW-positive.

Disclosures
David Seftel, M.D., M.D., M.B.A., Enable Biosciences, Inc (Board Member, Employee, Scientific Research Study Investigator, Shareholder)
367. Role of Conventional Biomarker for Prediction of Chest CT-confirmed COVID-19 Pneumonia
Authors: Harnphadungkit Monprach , Siripongboonsitti Taweegrit 
Published: December 2021

Abstract

Background
The coronavirus disease 2019 (COVID-19) has a wide range of severity. Chest computed tomography (CT) had high sensitivity and specificity to identify COVID-19 pneumonia. However, chest CT was not available in almost all hospitals in pandemic settings, including developed countries. This study is to evaluate the potential role of conventional inflammatory biomarkers to predict COVID-19 pneumonia.

Methods
All 155 RT-PCR-confirmed COVID-19 patients were evaluated for pneumonia by chest CT from April 10, 2021 to May 3, 2021 in the outpatient unit, a Thai university hospital. The inflammatory biomarkers were evaluated the sensitivity, specificity, LR+, LR-, and ROC to predict COVID-19 pneumonia.

Results
Of all 155 patients, pneumonia was diagnosed by chest CT in 117 patients. The pneumonia patients had a median (IQR) age of 38 (30, 55) years old. The BMI was higher in pneumonia than mild illness in 25.5 (22.0, 29.5) and 22.9 (19.4, 26.9) kg/m2, respectively (p=0.031). In univariate analysis, serum high-sensitivity C-reactive protein (hsCRP), lactate dehydrogenase (LDH), ferritin, total lymphocyte count (TLC), and albumin were associated with pneumonia, but the only hsCRP demonstrated association by multivariate analysis. The area under the ROC curves (AUC) was 0.82, 0.74, 0.68, 0.38, and 0.37 in hsCRP, LDH, ferritin, TLC, and albumin, respectively. The optimal cut-off level for CRP to diagnose COVID-19 pneumonia was 2.00 mg/L given sensitivity, specificity, LR+, LR- of 81.9%, 70.3%, 2.75, and 0.26 respectively (Figure 1 and Table 1).
ROC Curve of hsCRP to Diagnose of COVID-19 Pneumonia

This figure shows ROC curve for hsCRP to diagnose of chest CT-confirmed COVID-19 pneumonia. The area under the ROC curve is 0.82. The optimal cut-off value for hsCRP is 2.00 given sensitivity of 81.9% and specificity of 70.3%.

Conclusion
The hsCRP was the conventional biomarker that had an excellent performance in predicting COVID-19 pneumonia lead to early anti-SARS-CoV-2 treatment. This study demonstrated the potential role of hsCRP combined with clinical assessment in negative chest X-rays to replace chest CT in a high burden COVID-19 country during pandemic situations.

Disclosures
All Authors: No reported disclosures
370. Examining the Relationship Between SARS-CoV-2 PCR Cycle Threshold, Disease Severity and Epidemiologic Trends
Authors: Penney Jessica , Jung Amanda , Koethe Benjamin , Doron Shira 
Published: December 2021

Abstract

Background
Real-time reverse transcriptase PCR (rRT-PCR) has become the primary method for detection of SARS-CoV-2. Specific measurements of cycle threshold (Ct) values can give an estimate of viral load. Previous studies have shown temporal trends in Ct values, which could be used to predict the phase of the pandemic. This study’s goal was to examine the relationship between Ct and disease severity, as well as Ct trends.

Methods
Testing was performed using the Abbott M2000 SARS-CoV-2 assay. Data was collected for 262 SARS-CoV-2 positive patients from March-May 2020. Kruskal-Wallis testing was performed to determine differences in median Ct based on age, gender, race and ethnicity. To determine relationship between symptom onset and clinical severity with Ct, linear and logistic regression were performed.

Results
The majority of the patients had mild to moderate disease. Average time since symptom onset was 5.9 days, and 92% were symptomatic. Figure 1 demonstrates the distribution of Ct by disease severity at time of testing. There was no significant difference in cycle threshold by sex, age, race or ethnicity. Figure 2 shows weekly mean cycle threshold by total new cases in Massachusetts to reflect temporal trend of Ct and cases. In the multivariable linear regression model, Ct increased with days since symptom onset (P&lt; 0.001). Cycle threshold was inversely associated with disease severity in multivariable logistic regression though (OR 1.06, 95%CI 1.01-1.11, p=0.03), even when controlling for time since symptom onset.
Figure 1. Distribution of Ct by disease severity at time of SARS-CoV-2 testing

Boxplot demonstrating distribution of Ct by disease severity at time of testing. There was no significant difference between groups.
Figure 2. Weekly Mean Cycle Threshold by Total New MA Cases

Line represents mean Ct over time period included in this study overlaid on total new cases in Massachusetts. Lower Ct were seen in the course as cases were increasing which peaked as cases stabilized.

Conclusion
Cycle threshold increased with time since symptom onset, consistent with prior data showing increasing Ct from time since infection due to decreasing viral replication. This study showed an inverse relationship between cycle threshold and disease severity, which differs from previous studies which demonstrated higher odds of progression to severe disease and mortality with lower Ct. This finding may reflect the disease severity associated with the secondary inflammatory phase of SARS-CoV-2 seen later in the disease course, although there was only moderate correlation between Ct and time since symptom onset. Further research is needed to better understand the role of Ct in predicting clinical severity of SARS-CoV-2 infections.

Disclosures
All Authors: No reported disclosures
372. Detection of SARS-CoV-2 RNAemia in Deceased Tissue Donors
Authors: Greenwald Melissa , Grebe Eduard , Green Valerie , Jones Alyce Linthurst , Williamson Philip , Busch Michael , Kuehnert Matthew 
Published: December 2021

Abstract

Background
Tissue donors are evaluated for communicable disease in order to minimize the risk of transmission to recipients. Although there are data suggesting SARS-CoV-2 viremia across a wide spectrum of illness, prevalence in deceased tissue donors and the potential for transplant transmission are unknown.

Methods
Eight tissue banks participated in a retrospective analysis of samples from eligible deceased tissue donors from Oct 2019 through June 2020, one participant in Canada and the remainder located in the United States. All four Census regions of the continental US and all major racial-ethnic groups were represented. EDTA or sodium citrate plasma aliquots were tested in singlicate with the Research Use Only Procleix SARS-CoV-2 Assay on the Procleix Panther System, which uses transcription-mediated nucleic acid amplification (TMA) technology for detection of the SARS-CoV-2 RNA. Plasma (or if unavailable, serum) aliquots were sent to Grifols for an alternate SARS-CoV-2 nucleic acid amplification (NAT) test to verify reactivity and also sent for antibody testing using the emergency use authorization Ortho VITROS Immunodiagnostic Products Anti-SARS-CoV-2 Total test. The VITROS assay uses immunometric technology for qualitative measurement of total antibody (IgG, IgA and IgM) to SARS-CoV-2. The proportion of donors with confirmed RNAemia (i.e., presence of SARS-CoV-2 RNA in plasma or serum) and 95% confidence intervals were computed.

Results
Of 3,455 donor samples with valid final results, 26 (0.76%) were initially positive for SARS-CoV-2 RNA; of these, 3 were confirmed by alternate NAT. Of donor samples collected in 2019 0.00% (95% CI: 0.00%,0.43%) were confirmed RNAemic, while of those collected in 2020, 0.12% (0.04%,0.34%) were confirmed RNAemic. One of 26 initial positive, and none of the three samples confirmed by alternate NAT, tested positive for anti-SARS-CoV-2 Spike antibodies by serology. Infectivity studies are pending on one sample with sufficient available volume.

Conclusion
The rate of SARS-CoV-2 RNAemia in deceased tissue donors is approximately 1 per 1,000, and it is unknown whether this RNAemia reflects the presence of infectious virus. Given these results, the risk of transmission through tissue is most likely to be low.

Disclosures
Melissa Greenwald, MD, Alamo Biologics (Consultant)Eurofins VRL Laboratories (Consultant)Right Cell Biologics (Consultant, Consultant Medical Director) Eduard Grebe, PhD, Gilead Sciences (Consultant)Sedia Biosciences Corporation (Consultant, Grant/Research Support)Vitalant (Employee) Alyce Linthurst Jones, PhD, LifeNet Health (Employee) Matthew Kuehnert, MD, American Association of Tissue Banks (Board Member)ICCBBA (Board Member)Musculoskeletal Transplant Foundation (Employee)
373. Household transmission of SARS-CoV-2 B.1.1.7 lineage –2 U.S. States, 2021
Authors: Soto Raymond , Hsu Christoper , Chuey Meagan , Donnelly Marisa , Chu Victoria T , Schwartz Noah G , Tong Suxiang , Thornburg Natalie J , Killerby Marie E , Staples J Erin , Kirking Hannah L , Tate Jacqueline , Matanock Almea , Stringer Ginger , Albanese Bernadette , Beatty Mark , Hughes Laura J 
Published: December 2021

Abstract

Background
In December 2020, B.1.1.7 lineage of SARS-CoV-2 was first detected in the United States and has since become the dominant lineage. Previous investigations involving B.1.1.7 suggested higher rates of transmission relative to non-B.1.1.7 lineages. We conducted a household transmission investigation to determine the secondary infection rates (SIR) of B.1.1.7 and non-B.1.1.7 SARS-CoV-2 lineages.

Methods
From January–April 2021, we enrolled members of households in San Diego County, CA, and Denver, CO metropolitan area (Tri-County), with a confirmed SARS-CoV-2 infection in a household member with illness onset date in the previous 10 days. CDC investigators visited households at enrollment and 14 days later at closeout to obtain demographic and clinical data and nasopharyngeal (NP) samples on all consenting household members. Interim visits, with collection of NP swabs, occurred if a participant became symptomatic during follow-up. NP samples were tested for SARS-CoV-2 using TaqPath™ RT-PCR test, where failure to amplify the spike protein results in S-Gene target failure (SGTF) may indicate B.1.1.7 lineage. Demographic characteristics and SIR were compared among SGTF and non-SGTF households using two-sided p-values with chi-square tests; 95% confidence intervals (CI) were calculated with Wilson score intervals.

Results
552 persons from 151 households were enrolled. 91 (60%) households were classified as SGTF, 57 (38%) non-SGTF, and 3 (2%) indeterminant. SGTF and non-SGTF households had similar sex distribution (49% female and 52% female, respectively; P=0.54) and age (median 30 years, interquartile range (IQR 14–47) and 31 years (IQR 15–45), respectively). Hispanic people accounted for 24% and 32% of enrolled members of SGTF and non-SGTF households, respectively (p=0.04). At least one secondary case occurred in 61% of SGTF and 58% of non-SGTF households (P=0.66). SIR was 52% (95%[CI] 46%-59%) for SGTF and 45% (95% CI 37%-53%) for non-SGTF households (P=0.18).

Conclusion
SIRs were high in both SGTF and non-SGTF households; our findings did not support an increase in SIR for SGTF relative to non-SGTF households in this setting. Sequence confirmed SARS-CoV-2 samples will provide further information on lineage specific SIRs.

Disclosures
All Authors: No reported disclosures
374. Need to Improve Minority Representation through COVID-19 Community Research Partnership
Authors: Dantuluri Keerti , Rossman Whitney , Lu Lauren C , Dunn Connell O , Harris Anna M , Hetherington Timothy , Priem Jennifer , Ahmed Amina , Ahmed Amina 
Published: December 2021

Abstract

Background
Minorities are often unrepresented in research, which limits equity in healthcare advances. The racial and ethnic disparities in outcomes of individuals infected with COVID-19 highlight the importance of inclusivity in research to improve public health measures.

Methods
We performed a descriptive analysis of the racial and ethnic distribution of children enrolled in our COVID-19 Community Research Partnership (CRP) study, a syndromic and serological surveillance study of children aged 2 – 17 years receiving care at three healthcare systems spanning North and South Carolina. Syndromic surveillance involved daily symptom reporting using a web-based monitoring application. Participants consenting to serological surveillance were mailed at-home tests sampling finger prick capillary blood. In-person and electronic recruitment efforts were conducted in English and Spanish. At one of the study sites, we compared the racial/ethnic distribution of enrolled children to the racial/ethnic distribution of all children who received care at the same site during the same timeframe. We compared the racial/ethnic distribution of participants who ultimately submitted samples for serological testing compared to those who consented to serologic testing.

Results
At total of1630 children were enrolled from April 2, 2021 – June 8, 2021. Most children were &gt; 5 years old, 50.2% were female, and 88.5% were from mostly urban counties (Table 1). Of enrolled children, 4.2% were Hispanic, 8.2% were black, and 81.6% were white (Table 2). Among 135,355 unique children who received care at the institution during the same time, 12.4% were Hispanic, 23.0% were black, and 63.1% were white. Of 1552 participants who consented to serologic testing, 4.4% were Hispanic, 8.1% were black, and 81.8% were white (Table 3). To date, 242 children submitted serologic samples; 4.1% were Hispanic, 5.0% were black, and 85.5% were white.
Table 1. Characteristics of enrolled children in COVID-19 surveillance study

Table 2. Racial and Ethnic distribution of children enrolled in the study compared to target population

Table 3. Racial and ethnic distribution of children who participated in serology testing

Conclusion
Despite efforts to recruit a diverse group of children, the proportion of minorities enrolled in our COVID-19 surveillance study underrepresents the targeted population. Ongoing efforts will work to identify barriers and facilitators to research participation among minority families.

Disclosures
Amina Ahmed, MD, Nothing to disclose
375. High Laboratory-confirmed SARS-CoV-2 Attack Rate in Lima Health Care Personnel During August 2020-March 2021 Suggests Role for Improved Infection Control
Authors: Westercamp Matthew , Soto Giselle , Smith Rachel , Azziz-Baumgartner Eduardo , Bollinger Susan , Castillo Roger , Cuentas Alejandro Llanos , Grogl Max , Olson Natalie , Prouty Mike , Matos Eduardo , Romero Candice , Silva Marita , Lessa Fernanda C , Lessa Fernanda C , Arriola Carmen S 
Published: December 2021

Abstract

Background
Peru has one of the highest per capita SARS-CoV-2 death rates in Latin America. Healthcare workers (HCW) are a critical workforce during the COVID-19 pandemic but are themselves often at increased risk of infection. We evaluated SARS-CoV-2 attack rate and risk factors among frontline HCWs.

Methods
We performed a prospective cohort study of HCW serving two acute care hospitals in Lima, Peru from Aug 2020 to Mar 2021. Participants had baseline SARS-CoV-2 serology using the CDC ELISA, active symptom monitoring, and weekly respiratory specimen collection with COVID-19 exposure/risk assessment for 16-weeks regardless of symptoms. Respiratory specimens were tested by real-time reverse transcriptase PCR (rRT-PCR).

Results
Of 783 eligible, 667 (85%) HCW were enrolled (33% nurse assistants, 29% non-clinical staff, 26% nurses, 7% physicians, and 6% other). At baseline and prior to COVID-19 vaccine introduction, 214 (32.1%; 214/667) were reactive for SARS-CoV-2 antibodies. In total, 72 (10.8%; 72/667) HCWs were found to be rRT-PCR positive during weekly follow-up. Of the rRT-PCR positive HCWs, 37.5% (27/72) did not report symptoms within 1-week of specimen collection. During follow up, HCW without detectable SARS-CoV-2 antibodies at baseline were significantly more likely to be rRT-PCR positive (65/453, 14.3%) compared to those with SARS-CoV-2 antibodies at baseline (4/214, 1.9%) (p-value: &lt; 0.001). Three HCW were both serologically reactive and rRT-PCR positive at baseline. Looking only at HCW without SARS-CoV-2 antibodies, nurse assistants (rRT-PCR positive: 18.6%; 27/141) and non-clinical healthcare workers (16.5%; 21/127) were at greater risk of infection compared to nurses (8.5%; 10/118), physicians (7.9%; 3/38), and other staff (10.3%; 4/29) (RR 1.95;95%CI 1.2,3.3; p-value: 0.01).

Conclusion
Baseline SARS-CoV-2 prevalence and 16-week cumulative incidence were substantial in this pre-vaccination Peruvian HCW cohort. Almost 40% of new infections occurred in HCW without complaint of symptoms illustrating a limitation of symptom-based HCW screening for COVID-19 prevention. Nurse assistants and non-clinical healthcare workers were at greater risk of infection indicating a role for focused infection prevention and risk reduction strategies for some groups of HCW.

Disclosures
Fernanda C. Lessa, MD, MPH, Nothing to disclose