The 2021 SIIM-FISABIO-RSNA Machine Learning COVID-19 Challenge: Annotation and Standard Exam Classification of COVID-19 Chest Radiographs.

We describe the curation, annotation methodology, and characteristics of the dataset used in an artificial intelligence challenge for detection and localization of COVID-19 on chest radiographs. The chest radiographs were annotated by an international group of radiologists into four mutually exclusive categories, including "typical," "indeterminate," and "atypical appearance" for COVID-19, or "negative for pneumonia," adapted from previously published guidelines, and bounding boxes were placed on airspace opacities. This dataset and respective annotations are available to researchers for academic and noncommercial use.

Pilot Study of Lymphocyte Subset Analysis in COVID-19 Patients Presenting to a Tertiary Hospital

Introduction: A reduced absolute lymphocyte count in peripheralblood along with relative increase in neutrophil count has beenobserved consistently in hospitalized COVID-19 patients. The role ofbaseline lymphocyte subsets in COVID-19 is still unknown.Aims &Objectives: We aimed at analyzing the baseline lymphocytesubsets in COVID-19 patients and its impact on the outcome andseverity of the disease.Materials &Methods: Study was conducted retrospectively fromhospital electronic records. Diagnosis of COVID-19 disease wasbased on the RTPCR for SARS-COV-2 virus. Lymphocyte subsetswere determined using flowcytometry in COVID-19 patients onadmission to COVID ward. The variation in the baseline lymphocytesubsets according to the severity and outcome of the disease wasanalyzed.Result: Patients who died of COVID-19 disease had higher mean Blymphocytes and NK cells than the survivors but was not statisticallysignificant. T lymphocyte counts and CD8 + T cell counts showedstatistically significant (p< 0.05) reduction in patients who expiredthan who survived COVID-19 disease.Conclusions: We concluded that low CD8 + T cell counts atadmission may be predictive of patient outcomes in COVID-19.

Mimickers of Hit Antibodies in Critically Ill COVID Patients

Introduction: Infection with SARS CoV2 leads to respiratory failureand can lead to support of extracorporeal oxygenation (ECMO)leading to exposure to heparin. Exposure to heparin and developmentof thrombocytopenia raises the suspicion of HIT. The strong positiveIgG PF4-heparin antigen test by immunochromatography is followedby platelet aggregation test in our center. We present a case of covid-19 in which HIT was strongly positive on gel agglutination butfunctional assay was negative. Review of literature shows that this could be due to circulating platelet immune complexes in critically illcovid patients which simulate HIT antibodies.Aims &Objectives: Materials &Methods: 7 months pregnantfemale, non-vaccinated, asthmatic, COVID 19 positive patient wasadmitted to our hospital. On admission her fetal ultrasound wasnormal and was started on non-invasive ventilation along with supportive care. However she deteriorated and shifted to veno-arterialextracorporeal membrane oxygenation support (ECMO). Her plateletcount dropped by>50% at day 6 of heparin exposure with anintermediate probability for HIT (4Tscore 5). HIT gel agglutinationtest was positive for IgG antibodies for antiheparin/PF4 antibodies butfunctional assay based on heparin-induced platelet aggregation(HIPA) revealed no increase in aggregation of patient serum with0.5U/ml and 1U/ml heparin dosage. Heparin induced thrombocytopenia was ruled out due to PAT and patient continued on ECMO.This could be due to increased platelet activating immune complexesor anti-PF4 antibodies mimicking antiheparin/PF4 antibodies. However, patient deteriorated and succumbed to the disease.Result: Heparin induced thrombocytopenia was ruled out due to PATand patient continued on ECMO. This could be due to increasedplatelet activating immune complexes or anti-PF4 antibodies mimicking antiheparin/PF4 antibodies. However, patient deteriorated andsuccumbed to the disease.Conclusions: Pathophysiology of Covid 19 disease in critical caseshas shown exacerbated immune reactions, increased endothelialinjury, which causes increased release of PF4 leading to plateletactivation.3 A recent work has also shown significantly increasedplatelet apoptosis, secondary to IgG-mediated FccRIIA signaling, incritically ill COVID-19 patients.4 It is also possible that the circulating immune complexes may be formed by corona virus-antibodycomplexes (as seen in H1N1 viral infection) 0.5 A high titre of antiPF4/heparin antibody test may not strongly predict the presence ofclinically relevant HIT antibodies, thus a confirmatory functional testshould be performed.

The next big earthquake may inflict a multi-hazard crisis - Insights from COVID-19, extreme weather and resilience in peripheral cities of Israel.

The occurrence of a natural disaster in an area already coping with an epidemic, constitutes a multi-hazard event. Such events are more likely than ever during the ongoing COVID-19 pandemic. In regions that seasonally experience extreme-weather disasters, such multi-hazard crises are imminent. People living along the Dead Sea Fault and in the Negev are used to harsh weather conditions and to the hardship of living in isolation. While self-reliance and community-support are often the norm in the daily life of residents in in peripheral communities, in an emergency they may be crucial for survival. Worldwide remote communities with limited response and medical infrastructure and resources may struggle to cope with the aftermath of an earthquake while potentially coping with a concurrent epidemic or extreme weather. In this work we focus on the effect of concurring disasters and seasonal stressors. In particular we discuss how various disasters would affect the Covid-19 infection rate, and we demonstrate that in Israel's periphery cities, heat-stress is a consistent and significant seasonal stressor that would hamper emergency and recovery operations. We also suggest that transient tourist population in these remote cities is expected to burden local emergency efforts and facilities. A seasonal over burden parameter is proposed to describe how seasonal tourism and weather conditions enhance the hardship and risk in a multi-hazard situation. A case study shows that high-resolution spatial analysis of risk and preparedness together with a temporal analysis of seasonal effects, may be used to detect specific neighborhoods with high or low resilience and capacity to cope with disasters. Our work demonstrates the need for spatial and temporal, multi-hazard analysis for improving local resilience and emergency plans in periphery cities and communities exposed to seasonal harsh weather.

Towards Risk Indication in Mountain Biking Using Smart Wearables

Mountain biking as a recreational sport is currently thriving. During the ongoing COVID-19 pandemic, even more people started compensating for a lack of activity through individual outdoor sports, such as cycling. However, when executed beyond paved forest roads, mountain biking is a sport with subjective and objective risks, in which crashes often can not be entirely avoided and athletes may get injured. In this late-breaking work, we showcase a concept for a crash risk indication application for sports smartwatches. First, we review a wide range of related work, which formed the basis for our crash risk indication metric. We discuss options for the sensor-based detection of internal and external risk factors and propose a way to aggregate them, which will allow dynamic and potentially automatic fine-tuning by observing or obtaining feedback from the athlete. In addition, we present a concept for a smartwatch application that will provide constant feedback and an unobtrusive signal to the athlete when an unusually high risk is detected. Finally, we give an outlook on the necessary steps to implement our approach as a smartwatch app. © 2021 ACM.

Convalescent plasma, cytomegalovirus infection, and persistent leukopenia in COVID-19 recovery phase: What is the link?

Therapies used to tide over acute crisis of COVID-19 infection may lower the immunity, which can lead to secondary infection or a reactivation of latent infection. We report a 75-years-old male patient who had suffered from severe COVID-19 infection three weeks earlier and who had been treated with corticosteroids and convalescent plasma along with other supportive therapies. At time of discharge he had developed leukopenia which worsened at 1-week follow up visit. On 18th day post-discharge, he became very sick and was brought to our hospital with complaints of severe persistent dysphagia. During evaluation he was diagnosed to have an acute cytomegalovirus infection and severe oropharyngeal thrush. Both COVID-19 and cytomegalovirus are known to cause synergistic decrease in T cells and NK cells leading to immunosuppression. The patient made complete recovery with a course of intravenous ganciclovir and fluconazole. Persistent leukopenia in high risk and severely ill cases should give rise to a suspicion of COVID-19 and cytomegalovirus co-infection.

Physical Activity Among Predominantly White Middle-Aged and Older US Adults During the SARS-CoV-2 Pandemic: Results From a National Longitudinal Survey

Background: The first COVID-19 case in the US was diagnosed late January 2020. In the subsequent months, cases grew exponentially. By March 2020, SARS-CoV-2 (the novel coronavirus that causes COVID-19) was a global pandemic and the US declared a national emergency. To mitigate transmission, federal guidelines were established for social and physical distancing. These events disrupted daily routines of individuals around the world, including Americans. The impact of the pandemic on PA patterns of Americans is largely unknown, especially among those at greater risk for severe COVID-19 outcomes. The aim of this study was to assess levels of PA over time during the pandemic among US adults aged >50 years.

Sars-cov-2 associated with cmv reactivation-proof of immune dysregulation;''amalgamation of past and present''

Aims & Objectives: To study the immune profile of SARS-CoV-2 patients with recent & active CMV infection. Patients/Materials & Methods: The immune profile of three SARSCoV-2 patients with persistent lymphopenia and increased CMV copy numbers were analysed using single platform flowcytometry, The patients were also evaluated for acute phase reactants such as IL-6, CRP, LDH and Ferritin levels. Other tests like PT, APTT, D-Dimer & Fibrinogen for coagulopathies were also correlated. The patients were exhaustively evaluated for underling comorbities. Results: The lymphocyte subset counts in SARS-CoV-2 patients showed markedly reduced CD4 and CD8 counts with mean CD4 counts 260 cells/microL and CD8 counts of 126 cells/microL. The patients were CMV positive with copy numbers ranging from 149 to 217 AU/mL. The IL-6, CRP, Ferritin values were elevated in all with normal LDH and Procalcitonin values. D-dimer levels were elevated with normal PT, APTT&Fibrinogen levels. The mean of IL-6,CRP and ferritin were : 286.86 pg/mL,112 mg/L,197.35 ng/mL respectively. All our patients had comorbidities like diabetes mellitus, hypertension and cardiovascular disease. These patients were all treated with injection Gancyclovir and patient showed steady improvement clinically and TLC counts reached the normal range within few days of initiating treatment with progressive reduction in CMV copies. Discussion & Conclusion: The common hematological feature of SARS-CoV-2 is leucocytosis with absolute lymphopenia & high neutrophil to lymphocyte ratio. However, studies have shown that persistent leucopenia is associated with secondary and opportunistic infections. The novel corona virus affect the T cell subset especially CD8 + T lymphocytes causing lymphopenia by either excessive recruitment to peripheral pathways, hyper activation by inflammatory cytokines or increased pro-apoptotic signaling by Caspase 3 and CD59. Immune dysregulation in SARS-CoV-2 patients may lead to reactivation of CMV. It has also been speculated that rampant use of anti IL-1 and anti-IL6 and immunomodifying drugs such as Favipravir might be playing an important role in reactivation of CMV virus. Conclusion: A CMV screening in all the high risk patients, persistent or increasing leucopenia and in ICU setting might help in reducing the percentage and degree of mortality and complications the patient might suffer from. A timely diagnosis and treatment with an eyesight for detection of early complication may help in this battle with SARSCoV-2.