Explainable Machine Learning Model to Preoperatively Predict Postoperative Complications in Inpatients With Cancer Undergoing Major Operations.

PURPOSE: Preoperative prediction of postoperative complications (PCs) in inpatients with cancer is challenging. We developed an explainable machine learning (ML) model to predict PCs in a heterogenous population of inpatients with cancer undergoing same-hospitalization major operations. METHODS: Consecutive inpatients who underwent same-hospitalization operations from December 2017 to June 2021 at a single institution were retrospectively reviewed. The ML model was developed and tested using electronic health record (EHR) data to predict 30-day PCs for patients with Clavien-Dindo grade 3 or higher (CD 3+) per the CD classification system. Model performance was assessed using area under the receiver operating characteristic curve (AUROC), area under the precision recall curve (AUPRC), and calibration plots. Model explanation was performed using the Shapley additive explanations (SHAP) method at cohort and individual operation levels. RESULTS: A total of 988 operations in 827 inpatients were included. The ML model was trained using 788 operations and tested using a holdout set of 200 operations. The CD 3+ complication rates were 28.6% and 27.5% in the training and holdout test sets, respectively. Training and holdout test sets' model performance in predicting CD 3+ complications yielded an AUROC of 0.77 and 0.73 and an AUPRC of 0.56 and 0.52, respectively. Calibration plots demonstrated good reliability. The SHAP method identified features and the contributions of the features to the risk of PCs. CONCLUSION: We trained and tested an explainable ML model to predict the risk of developing PCs in patients with cancer. Using patient-specific EHR data, the ML model accurately discriminated the risk of developing CD 3+ complications and displayed top features at the individual operation and cohort level.

Recurrence patterns after complex multimodality therapy and hepatic arterial infusion for colorectal liver metastases: A reflection of biology and technique.

BACKGROUND AND METHODS: We characterized colorectal liver metastasis recurrence and survival patterns after surgical resection and intraoperative ablation ± hepatic arterial infusion pump (HAIP) placement. We estimated patterns of recurrence and survival in patients undergoing contemporary multimodal treatments. Between 2017 and 2021, patient, tumor characteristics, and recurrence data were collected. Primary outcomes included recurrence patterns and survival data based on operative intervention. RESULTS: There were 184 patients who underwent hepatectomy and intraoperative ablation. Sixty patients (32.6%) underwent HAIP placement. A total of 513 metastases were ablated, median total of 2 ablations per patient. Median time to recurrence was 31 [22-40] months. Recurrence patterns included tumor at ablative margin on first scheduled postoperative imaging (8, 4.3%), local tumor recurrence at ablative site (69, 37.5%), and non-ablated liver tumor recurrence (38, 20.6%). In patients who underwent HAIP placement, the rate of liver recurrence was reduced (45% vs 70.9%, p = 0.0001). Median overall survival was 64 [41-58] months and prolonged survival was associated with HAIP treatment (85 [66-109] vs 60 [51-70] months. CONCLUSIONS AND DISCUSSION: Hepatic recurrence is common and combination of intraoperative ablation and HAIP treatments were associated with prolonged survival. These data may reflect patient selection however, future work will clarify preoperative tumor and patient characteristics that may better predict recurrence expectations.

Multidisciplinary management of a pregnancy complicated by Glanzmann thrombasthenia: A case report.

BACKGROUND: Glanzmann thrombasthenia (GT) is a rare, autosomal recessive disorder of platelet glycoprotein IIb-IIIa receptors. Pregnant patients with GT are at increased risk of maternal and fetal bleeding. There is a paucity of literature on the peripartum management of patients. CASE DESCRIPTION: We present the antepartum through the postpartum course of a patient with GT who was managed by a multidisciplinary approach that included communication across maternal-fetal medicine, hematology, transfusion medicine, and anesthesiology services. In addition to routine prepartum obstetric imaging and hematologic laboratory studies, we proactively monitored the patient for anti-platelet antibodies every 4-6 weeks to gauge the risk for neonatal alloimmune thrombocytopenia. Furthermore, we prioritized uterotonics, tranexamic acid, and transfusion of HLA-matched platelets to manage bleeding for mother and fetus intrapartum through the postpartum periods. CONCLUSION: To date, there are limited guidelines for managing bleeding or preventing alloimmunization during pregnancy in patients with GT. Here, we present a complex case with aggressive management of bleeding prophylactically for the mother while serially monitoring both mother and fetus for peripartum bleeding risks and events. Moreover, future studies warrant continued evaluation of these approaches to mitigate increased bleeding risks in subsequent pregnancies.

Pilot study of HER2 targeted 64 Cu-DOTA-tagged PET imaging in gastric cancer patients.

OBJECTIVE: Human epidermal growth factor receptor 2 (HER2) is an important biomarker for targeted gastric cancer (GC) immunotherapy. However, heterogeneous HER2 overexpression in GC, loss of HER2 expression during therapy, and inability to non-invasively identify HER2 overexpressing tumors impede effective targeting therapies. Improved HER2-specific functional imaging can address these challenges. Trastuzumab is a HER2-directed mAb to treat HER2 overexpressing cancers. The 64 Cu-DOTA-trastuzumab radiotracer is used to detect HER2+ metastatic breast cancer. We aimed to develop 64 Cu-DOTA-trastuzumab PET-CT to detect and characterize tumor uptake in HER2+ or - GC patients. METHODS: We conducted a single-arm phase II pilot study exploring the feasibility of 64 Cu-DOTA-trastuzumab for PET imaging of HER2 overexpressing GC compared to HER2 non-expressing tumors. Eight patients with biopsy-confirmed gastric adenocarcinoma were included. Immunohistochemistry was used to evaluate primary tumor biopsies for HER2 overexpression. Patients were injected with 45 mg of cold trastuzumab followed by 5 mg of 64 Cu-DOTA-trastuzumab. PET-CT scans were performed 24-48 h post radiotracer injection and compared to standard staging CT scans. RESULTS: We observed limited toxicity following 64 Cu-DOTA-trastuzumab injections. While there was uptake of the radiotracer in portions of HER2+ lesions, there was no statistically significant distinction between tumor and background by standardized uptake value analysis. CONCLUSION: Despite the potential of 64 Cu-DOTA-trastuzumab PET imaging of HER2+ metastatic breast cancer, a 5 mg dose of this radiotracer injected 24-48 h before imaging was insufficient to identify HER2+ GC. These results inform future GC imaging studies to optimize biomarker-targeted therapies based on dosage and timing for more clinically relevant imaging.

Characterization of infectious and non-infectious gastrointestinal disease in common variable immunodeficiency: analysis of 114 patient cohort.

Common Variable Immunodeficiency (CVID), a complex primary immunodeficiency syndrome defined by defective B cell responses to infection and vaccination, has heterogeneous clinical manifestations. Gastrointestinal (GI) complications in CVID, both infectious and non-infectious, can cause significant impairment leading to malabsorption and frank malnutrition. In order to better characterize the spectrum of GI disease associated with CVID, we describe 114 patients with GI disease (15.6%) from our 728 patient single center CVID cohort. Norovirus, Giardia and Cytomegalovirus were the most frequently isolated infectious pathogens. CVID enteropathy was the most encountered GI diagnosis based on endoscopy, with only a minority of patients having Crohn's disease (6.1%) or ulcerative colitis/proctitis (4.5%). Concurrent autoimmunity (30.7%), lung disease (18.4%) and malignancy (8.7%) were also present in significant proportion of subjects. Lastly, 16 of 47 (34%) who underwent whole exome sequencing demonstrated a culprit gene defect associated with CVID.

Therapeutic Efficacy of Temsirolimus in a Patient-derived Model of Metastatic Fibrolamellar Hepatocellular Carcinoma.

BACKGROUND/AIM: Fibrolamellar hepatocellular carcinoma (FLHCC) is a rare tumor presenting in younger patients without chronic liver disease. Up to 80-100% develop recurrent disease, necessitating additional surgery or systemic treatment. Systemic options and pre-clinical treatment studies are lacking. We previously described patient-derived xenograft (PDX) development, allowing for pre-clinical studies. Herein, we develop FLHCC PDX models and utilize these to define tumor characteristics and determine the efficacy of systemic agents. MATERIALS AND METHODS: Primary and lymph node metastatic tumor tissues were obtained at the time of FLHCC resection in two patients. Tumor lysates were screened for protein upregulation. Cell lines were generated from metastatic and primary tumor tissue. The viability of the cell lines was assessed after treatment with temsirolimus, gemcitabine/oxaliplatin, and FOLFIRINOX. Two PDX models were developed from metastatic tissue. For in vivo studies, tumor-bearing mice were treated with temsirolimus, FOLFIRINOX, and Gemcitabine/oxaliplatin. RESULTS: PDX models were successfully generated from metastatic FLHCC, which closely recapitulated the original tumor. Upregulation of mTOR was seen in metastatic tissue compared to primary tumors. Cell lines from metastatic tissue demonstrated significant sensitivity to temsirolimus. In vivo testing of PDX models demonstrated a significant response to single-agent temsirolimus with minimal toxicity. CONCLUSION: Herein, we demonstrate the feasibility of developing PDX models that closely recapitulate FLHCC. Upregulation of mTOR was seen in metastatic tissue compared to primary tissue. The efficacy of mTOR inhibition with temsirolimus treatment suggests that the upregulation of the mTOR pathway may be a significant mechanism for growth in metastatic lesions and a potential target for therapeutics.

Genomic and ultrastructural analysis of monkeypox virus in skin lesions and in human/animal infected cells reveals further morphofunctional insights into viral pathogenicity.

Monkeypox (MPOX) is a zoonotic disease that affects humans and other primates, resulting in a smallpox-like illness. It is caused by monkeypox virus (MPXV), which belongs to the Poxviridae family. Clinically manifested by a range of cutaneous and systemic findings, as well as variable disease severity phenotypes based on the genetic makeup of the virus, the cutaneous niche and respiratory mucosa are the epicenters of MPXV pathogenicity. Herein, we describe the ultrastructural features of MPXV infection in both human cultured cells and cutaneous clinical specimens collected during the 2022-2023 MPOX outbreak in New York City that were revealed through electron microscopy. We observed typical enveloped virions with brick-shaped morphologies that contained surface protrusions, consistent with the classic ultrastructural features of MPXV. In addition, we describe morpho-functional evidence that point to roles of distinct cellular organelles in viral assembly during clinical MPXV infection. Interestingly, in skin lesions, we found abundant melanosomes near viral assembly sites, particularly in the vicinity of mature virions, which provides further insight into virus-host interactions at the subcellular level that contribute to MPXV pathogenesis. These findings not only highlight the importance of electron microscopic studies for further investigation of this emerging pathogen but also in characterizing MPXV pathogenesis during human infection.

Low anterior resection syndrome.

Low anterior resection syndrome represents a clinical state wherein a constellation of gastrointestinal symptoms is a direct result of anatomic changes to the rectum. Patients who undergo operations to create a neorectum often develop persistent symptoms of increased frequency, urgency, diarrhea, and these symptoms are debilitating and impact patients' quality of life. A stepwise approach to treatment can improve many patients' symptoms with the most invasive options reserved for highly refractory symptoms.

Phylogenetic landscape of Monkeypox Virus (MPV) during the early outbreak in New York City, 2022.

Monkeypox (MPOX) is a zoonotic disease endemic to regions of Central/Western Africa. The geographic endemicity of MPV has expanded, broadening the human-monkeypox virus interface and its potential for spillover. Since May 2022, a large multi-country MPV outbreak with no proven links to endemic countries has originated in Europe and has rapidly expanded around the globe, setting off genomic surveillance efforts. Here, we conducted a genomic analysis of 23 MPV-infected patients from New York City during the early outbreak, assessing the phylogenetic relationship of these strains against publicly available MPV genomes. Additionally, we compared the genomic sequences of clinical isolates versus culture-passaged samples from a subset of samples. Phylogenetic analysis revealed that MPV genomes included in this study cluster within the B.1 lineage (Clade IIb), with some of the samples displaying further differentiation into five different sub-lineages of B.1. Mutational analysis revealed 55 non-synonymous polymorphisms throughout the genome, with some of these mutations located in critical regions required for viral multiplication, structural and assembly functions, as well as the target region for antiviral treatment. In addition, we identified a large majority of polymorphisms associated with GA > AA and TC > TT nucleotide replacements, suggesting the action of human APOBEC3 enzyme. A comparison between clinical isolates and cell culture-passaged samples failed to reveal any difference. Our results provide a first glance at the mutational landscape of early MPV-2022 (B.1) circulating strains in NYC.

Legal Firearm Sales at State Level and Rates of Violent Crime, Property Crime, and Homicides.

INTRODUCTION: The effects of firearm sales and legislation on crime and violence are intensely debated, with multiple studies yielding differing results. We hypothesized that increased lawful firearm sales would not be associated with the rates of crime and homicide when studied using a robust statistical method. METHODS: National and state rates of crime and homicide during 1999-2015 were obtained from the United States Department of Justice and the Centers for Disease Control and Prevention. National Instant Criminal Background Check System background checks were used as a surrogate for lawful firearm sales. A general multiple linear regression model using log event rates was used to assess the effect of firearm sales on crime and homicide rates. Additional modeling was then performed on a state basis using an autoregressive correlation structure with generalized estimating equation estimates for standard errors to adjust for the interdependence of variables year to year within a particular state. RESULTS: Nationally, all crime rates except the Centers for Disease Control and Prevention-designated firearm homicides decreased as firearm sales increased over the study period. Using a naive national model, increases in firearm sales were associated with significant decreases in multiple crime categories. However, a more robust analysis using generalized estimating equation estimates on state-level data demonstrated increases in firearms sales were not associated with changes in any crime variables examined. CONCLUSIONS: Robust analysis does not identify an association between increased lawful firearm sales and rates of crime or homicide. Based on this, it is unclear if efforts to limit lawful firearm sales would have any effect on rates of crime, homicide, or injuries from violence committed with firearms.

Evaluation and validation of an RT-PCR assay for specific detection of monkeypox virus (MPXV).

Monkeypox virus (MPXV) is a zoonotic orthopoxvirus within the Poxviridae family. MPXV is endemic to Central and West Africa. However, the world is currently witnessing an international outbreak with no clear epidemiological links to travel or animal exposure and with ever-increasing numbers of reported cases worldwide. Here, we evaluated and validated a new, sensitive, and specific real-time PCR-assay for MPXV diagnosis in humans and compare the performance of this novel assay against a Food & Drug Administration-cleared pan-Orthopox RT-PCR assay. We determined specificity, sensitivity, and analytic performance of the PKamp™ Monkeypox Virus RT-PCR assay targeting the viral F3L-gene. In addition, we further evaluated MPXV-PCR-positive specimens by viral culture, electron microscopy, and viral inactivation assays. The limit of detection was established at 7.2 genome copies/reaction, and MPXV was successfully identified in 20 clinical specimens with 100% correlation against the reference method with 100% sensitivity and specificity. Our results demonstrated the validity of this rapid, robust, and reliable RT-PCR assay for specific and accurate diagnosis of MPXV infection in human specimens collected both as dry swabs and in viral transport media. This assay has been approved by NYS Department of Health for clinical use.

A Robust, Highly Multiplexed Mass Spectrometry Assay to Identify SARS-CoV-2 Variants.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are characterized by differences in transmissibility and response to therapeutics. Therefore, discriminating among them is vital for surveillance, infection prevention, and patient care. While whole-genome sequencing (WGS) is the "gold standard" for variant identification, molecular variant panels have become increasingly available. Most, however, are based on limited targets and have not undergone comprehensive evaluation. We assessed the diagnostic performance of the highly multiplexed Agena MassARRAY SARS-CoV-2 Variant Panel v3 to identify variants in a diverse set of 391 SARS-CoV-2 clinical RNA specimens collected across our health systems in New York City, USA and Bogotá, Colombia (September 2, 2020 to March 2, 2022). We demonstrated almost perfect levels of interrater agreement between this assay and WGS for 9 of 11 variant calls (κ ≥ 0.856) and 25 of 30 targets (κ ≥ 0.820) tested on the panel. The assay had a high diagnostic sensitivity (≥93.67%) for contemporary variants (e.g., Iota, Alpha, Delta, and Omicron [BA.1 sublineage]) and a high diagnostic specificity for all 11 variants (≥96.15%) and all 30 targets (≥94.34%) tested. Moreover, we highlighted distinct target patterns that could be utilized to identify variants not yet defined on the panel, including the Omicron BA.2 and other sublineages. These findings exemplified the power of highly multiplexed diagnostic panels to accurately call variants and the potential for target result signatures to elucidate new ones. IMPORTANCE The continued circulation of SARS-CoV-2 amid limited surveillance efforts and inconsistent vaccination of populations has resulted in the emergence of variants that uniquely impact public health systems. Thus, in conjunction with functional and clinical studies, continuous detection and identification are quintessential to informing diagnostic and public health measures. Furthermore, until WGS becomes more accessible in the clinical microbiology laboratory, the ideal assay for identifying variants must be robust, provide high resolution, and be adaptable to the evolving nature of viruses like SARS-CoV-2. Here, we highlighted the diagnostic capabilities of a highly multiplexed commercial assay to identify diverse SARS-CoV-2 lineages that circulated from September 2, 2020 to March 2, 2022 among patients seeking care in our health systems. This assay demonstrated variant-specific signatures of nucleotide/amino acid polymorphisms and underscored its utility for the detection of contemporary and emerging SARS-CoV-2 variants of concern.

A robust, highly multiplexed mass spectrometry assay to identify SARS-CoV-2 variants.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are characterized by differences in transmissibility and response to therapeutics. Therefore, discriminating among them is vital for surveillance, infection prevention, and patient care. While whole viral genome sequencing (WGS) is the "gold standard" for variant identification, molecular variant panels have become increasingly available. Most, however, are based on limited targets and have not undergone comprehensive evaluation. We assessed the diagnostic performance of the highly multiplexed Agena MassARRAY ® SARS-CoV-2 Variant Panel v3 to identify variants in a diverse set of 391 SARS-CoV-2 clinical RNA specimens collected across our health systems in New York City, USA as well as in Bogotá, Colombia (September 2, 2020 - March 2, 2022). We demonstrate almost perfect levels of interrater agreement between this assay and WGS for 9 of 11 variant calls (κ ≥ 0.856) and 25 of 30 targets (κ ≥ 0.820) tested on the panel. The assay had a high diagnostic sensitivity (≥93.67%) for contemporary variants (e.g., Iota, Alpha, Delta, Omicron [BA.1 sublineage]) and a high diagnostic specificity for all 11 variants (≥96.15%) and all 30 targets (≥94.34%) tested. Moreover, we highlight distinct target patterns that can be utilized to identify variants not yet defined on the panel including the Omicron BA.2 and other sublineages. These findings exemplify the power of highly multiplexed diagnostic panels to accurately call variants and the potential for target result signatures to elucidate new ones. Importance: The continued circulation of SARS-CoV-2 amidst limited surveillance efforts and inconsistent vaccination of populations has resulted in emergence of variants that uniquely impact public health systems. Thus, in conjunction with functional and clinical studies, continuous detection and identification are quintessential to inform diagnostic and public health measures. Furthermore, until WGS becomes more accessible in the clinical microbiology laboratory, the ideal assay for identifying variants must be robust, provide high resolution, and be adaptable to the evolving nature of viruses like SARS-CoV-2. Here, we highlight the diagnostic capabilities of a highly multiplexed commercial assay to identify diverse SARS-CoV-2 lineages that circulated at over September 2, 2020 - March 2, 2022 among patients seeking care at our health systems. This assay demonstrates variant-specific signatures of nucleotide/amino acid polymorphisms and underscores its utility for detection of contemporary and emerging SARS-CoV-2 variants of concern.

RT-PCR/MALDI-TOF Diagnostic Target Performance Reflects Circulating SARS-CoV-2 Variant Diversity in New York City.

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to circulate, multiple variants of concern have emerged. New variants pose challenges for diagnostic platforms because sequence diversity can alter primer/probe-binding sites (PBSs), causing false-negative results. The MassARRAY SARS-CoV-2 Panel (Agena Bioscience) uses RT-PCR and mass spectrometry to detect five multiplex targets across N and ORF1ab genes. Herein, we use a data set of 256 SARS-CoV-2-positive specimens collected between April 11, 2021, and August 28, 2021, to evaluate target performance with paired sequencing data. During this time frame, two targets in the N gene (N2 and N3) were subject to the greatest sequence diversity. In specimens with N3 dropout, 69% harbored the Alpha-specific A28095U polymorphism that introduces a 3'-mismatch to the N3 forward PBS and increases risk of target dropout relative to specimens with 28095A (relative risk, 20.02; 95% CI, 11.36 to 35.72; P < 0.0001). Furthermore, among specimens with N2 dropout, 90% harbored the Delta-specific G28916U polymorphism that creates a 3'-mismatch to the N2 probe PBS and increases target dropout risk (relative risk, 11.92; 95% CI, 8.17 to 14.06; P < 0.0001). These findings highlight the robust capability of MassARRAY SARS-CoV-2 Panel target results to reveal circulating virus diversity, and they underscore the power of multitarget design to capture variants of concern.

Validation of the American Association for the Surgery of Trauma Emergency General Surgery Grading System for Colorectal Resection: An EAST Multicenter Study.

BACKGROUND: The American Association for the Surgery of Trauma (AAST) has developed a grading system for emergency general surgery (EGS) conditions. We sought to validate the AAST EGS grades for patients undergoing urgent/emergent colorectal resection. METHODS: Patients enrolled in the "Eastern Association for the Surgery of Trauma Multicenter Colorectal Resection in EGS-to anastomose or not to anastomose" study undergoing urgent/emergent surgery for obstruction, ischemia, or diverticulitis were included. Baseline demographics, comorbidity severity as defined by Charlson comorbidity index (CCI), procedure type, and AAST grade were prospectively collected. Outcomes included length of stay (LOS) in-hospital mortality, and surgical complications (superficial/deep/organ-space surgical site infection, anastomotic leak, stoma complication, fascial dehiscence, and need for further intervention). Multivariable logistic regression models were used to describe outcomes and risk factors for surgical complication or mortality. RESULTS: There were 367 patients, with a mean (± SD) age of 62 ± 15 years. 39% were women. The median interquartile range (IQR) CCI was 4 (2-6). Overall, the pathologies encompassed the following AAST EGS grades: I (17, 5%), II (54, 15%), III (115, 31%), IV (95, 26%), and V (86, 23%). Management included laparoscopic (24, 7%), open (319, 87%), and laparoscopy converted to laparotomy (24, 6%). Higher AAST grade was associated with laparotomy (P = .01). The median LOS was 13 days (8-22). At least 1 surgical complication occurred in 33% of patients and the mortality rate was 14%. Development of at least 1 surgical complication, need for unplanned intervention, mortality, and increased LOS were associated with increasing AAST severity grade. On multivariable analysis, factors predictive of in-hospital mortality included AAST organ grade, CCI, and preoperative vasopressor use (odds ratio (OR) 1.9, 1.6, 3.1, respectively). The American Association for the Surgery of Trauma emergency general surgery grade was also associated with the development of at least 1 surgical complication (OR 2.5), while CCI, preoperative vasopressor use, respiratory failure, and pneumoperitoneum were not. CONCLUSION: The American Association for the Surgery of Trauma emergency general surgery grading systems display construct validity for mortality and surgical complications after urgent/emergent colorectal resection. These results support incorporation of AAST EGS grades for quality benchmarking and surgical outcomes research.

Hotspots for SARS-CoV-2 Omicron variant spread: Lessons from New York City.

The coronavirus disease-2019 (COVID-19) pandemic is still challenging public health systems worldwide, particularly with the emergence of novel SARS-CoV-2 variants with mutations that increase their transmissibility and immune escape. This is the case of the variant of concern Omicron that rapidly spread globally. Here, using epidemiological and genomic data we compared the situations in South Africa as the epicenter of emergence, United Kingdom, and with particular interest New York City. This rapid global dispersal from the place of first report reemphasizes the high transmissibility of Omicron, which needed only two weeks to become dominant in the United Kingdom and New York City. Our analyses suggest that as SARS-CoV-2 continues to evolve, global authorities must prioritize equity in vaccine access and continued genomic surveillance. Future studies are still needed to fully unveil the biological properties of Omicron, but what is certain is that vaccination, large-scale testing, and infection prevention efforts are the greatest arsenal against the COVID-19 pandemic.

Food for thought: Eating before saliva collection and interference with SARS-CoV-2 detection.

Saliva is a promising specimen for the detection of viruses that cause upper respiratory infections including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) due to its cost-effectiveness and noninvasive collection. However, together with intrinsic enzymes and oral microbiota, children's unique dietary habits may introduce substances that interfere with diagnostic testing. To determine whether children's dietary choices impact SARS-CoV-2 molecular detection in saliva, we performed a diagnostic study that simulates testing of real-life specimens provided from healthy children (n = 5) who self-collected saliva at home before and at 0, 20, and 60 min after eating 20 foods they selected. Each of 72 specimens was split into two volumes and spiked with SARS-CoV-2-negative or SARS-CoV-2-positive clinical standards before side-by-side testing by reverse-transcription polymerase chain reaction matrix-assisted laser desorption ionization time-of-flight (RT-PCR/MALDI-TOF) assay. Detection of internal extraction control and SARS-CoV-2 nucleic acids was reduced in replicates of saliva collected at 0 min after eating 11 of 20 foods. Interference resolved at 20 and 60 min after eating all foods except hot dogs in one participant. This represented a significant improvement in the detection of nucleic acids compared to saliva collected at 0 min after eating (p = 0.0005). We demonstrate successful detection of viral nucleic acids in saliva self-collected by children before and after eating a variety of foods. Fasting is not required before saliva collection for SARS-CoV-2 testing by RT-PCR/MALDI-TOF, but waiting for 20 min after eating is sufficient for accurate testing. These findings should be considered for SARS-CoV-2 testing and broader viral diagnostics in saliva specimens.

Profiling Selective Packaging of Host RNA and Viral RNA Modification in SARS-CoV-2 Viral Preparations.

Viruses package host RNAs in their virions which are associated with a range of functions in the viral life cycle. Previous transcriptomic profiling of host RNA packaging mostly focused on retroviruses. Which host RNAs are packaged in other viruses at the transcriptome level has not been thoroughly examined. Here we perform proof-of-concept studies using both small RNA and large RNA sequencing of six different SARS-CoV-2 viral isolates grown on VeroE6 cells to profile host RNAs present in cell free viral preparations and to explore SARS-CoV-2 genomic RNA modifications. We find selective enrichment of specific host transfer RNAs (tRNAs), tRNA fragments and signal recognition particle (SRP) RNA in SARS-CoV-2 viral preparations. Different viral preparations contain the same set of host RNAs, suggesting a common mechanism of packaging. We estimate that a single SARS-CoV-2 particle likely contains up to one SRP RNA and four tRNA molecules. We identify tRNA modification differences between the tRNAs present in viral preparations and those in the uninfected VeroE6 host cells. Furthermore, we find uncharacterized candidate modifications in the SARS-CoV-2 genomic RNA. Our results reveal an under-studied aspect of viral-host interactions that may be explored for viral therapeutics.

Human Anti-neuraminidase Antibodies Reduce Airborne Transmission of Clinical Influenza Virus Isolates in the Guinea Pig Model.

The public health burden caused by influenza virus infections is not adequately addressed with existing vaccines and antivirals. Identifying approaches that interfere with human-to-human transmission of influenza viruses remains a pressing need. The importance of neuraminidase (NA) activity for the replication and spread of influenza viruses led us to investigate whether broadly reactive human anti-NA monoclonal antibodies (MAbs) could affect airborne transmission of the virus using the guinea pig model. In that model, infection with recent influenza virus clinical isolates resulted in 100% transmission from inoculated donors to recipients in an airborne transmission setting. Anti-NA MAbs were administered either to the inoculated animals on days 1, 2, and 4 after infection or to the naive contacts on days 2 and 4 after donor infection. Administration of NA-1G01, a broadly cross-reactive anti-NA MAb, to either the donor or recipient reduced transmission of the A/New York City/PV02669/2019 (H1N1) and A/New York City/PV01148/2018 (H3N2) viruses. Administration of 1000-3C05, an anti-N1 MAb, to either the donor or recipient reduced transmission of A/New York City/PV02669/2019 (H1N1) virus but did not reduce transmission of A/New York City/PV01148 (H3N2) virus. Conversely, 229-2C06, an anti-N2 MAb, reduced transmission of A/New York City/PV01148 (H3N2) but did not impact transmission of A/New York City/PV02669/2019 (H1N1) virus. Our work demonstrates that anti-NA MAbs could be further developed into prophylactic or therapeutic agents to prevent influenza virus transmission to control viral spread. IMPORTANCE The burden of influenza remains substantial despite unremitting efforts to reduce the magnitude of seasonal influenza epidemics and prepare for pandemics. Although vaccination remains the mainstay of these efforts, current vaccines are designed to stimulate an immune response against the viral hemagglutinin. Interest in the role immunity against neuraminidase plays in influenza virus infection and transmission has recently surged. Human antibodies that bind broadly to neuraminidases of diverse influenza viruses and protect mice against lethal viral challenge have previously been characterized. Here, we show that three such antibodies inhibit the neuraminidase activity of recent isolates and reduce their airborne transmission in a guinea pig model. In addition to contributing to the accumulating support for incorporating neuraminidase as a vaccine antigen, these findings also demonstrate the potential of direct administration of anti-neuraminidase antibodies to individuals infected with influenza virus and to individuals for postexposure prophylaxis to prevent the spread of influenza virus.

Association of scooter-related injury and hospitalization with electronic scooter sharing systems in the United States.

INTRODUCTION: We used interrupted time series (ITS) analysis to determine whether e-scooter shares' introduction in September 2017 increased serious scooter-related injury across the United States. METHODS: Using the National Electronic Injury Surveillance System, we queried emergency department visits involving motorized scooter-related injuries from January 2010-December 2019. Cases originating where e-scooter shares launched between September 1, 2017-December 1, 2019 (intervention period) were considered exposed. The first month of launch (September 2017) was chosen as the time point for pre- and post-intervention analysis. The primary outcome was change in hospitalizations following scooter injury in association with the month/year launch. RESULTS: This analysis includes 2754 unweighted encounters, representing 102614 estimated injuries involving motorized scooters nationwide. Hospitals within 20 miles of e-scooter shares also experienced a significant monthly increase of 0.24 scooter-related injury hospitalizations/1000 product-related injury hospitalizations ([0.17,0.31]) compared to a non-significant change in hospitalizations of 0.02 [-0.05,0.09] for control hospitals. CONCLUSION: An increase in serious motorized scooter injuries coincides with e-scooter shares' introduction in the US. Future works should explore effective polices to improve public safety.